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Salivary gland cancer in Alaskan natives, 1966–1980
Perspectives in Pathology Salivary Gland Cancer in Alaskan Natives, 1966-1980 SARALA KRISHNAMURTHY,MD, MPH,* ANNE P. LANIER, MD, MPH,* PETER DOHAN, MD,t JAMES F. LANIER, MD,t AND WERNER HENLE. MDw T h e r e p o r t e d excess risk for salivary gland cancer among Eskimos l-s has been found to be due largely to the occurrence of malignant lymphoepithelial lesions (MLEL). 1,4,5 Ahhough this lesion has been reported to occur in other populations, 6-9 the largest series of cases to date have been reported in indigenous populations o f the arctic and subarctic regions and in southern China. 1-sA~ Malignant lymphoepithelial lesion shares histologic features with the benign lymphoepithelial lesion (BLEL), which may occur alone or in relation with Sj6gren's syndrome. 1~-13 The features of the benign lesions have been well characterized. 1~ Both malignant lymphoma 16A7 and epithelial tumors classified as MLEL have been reported in patients with BLEL. 6-9 Malignant lymphoepithelial lesion also shares some histologic similarities with nasopharyngeal carc i n o m a ) s Rates of this carcinoma in Eskimos are more than 15 times those in whites3 ,3 Nasopharyngeal carcinoma has been found to be associated with Epstein-Barr virus (EBV). 19 Because two reports h a v e s u g g e s t e d a r e l a t i o n b e t w e e n EBV a n d MLEL,e~ additional data on the presence of this virus in other patients with MLEL and BLEL would be of interest. All cases o f salivary gland cancers and BLEL among Alaskan Natives were reviewed, with special emphasis on lymphoepithelial lesions. This article presents results of epidenfiologic, clinical, and morphologic studies as well as tests for EBV, human leukocyte antigen (HLA), and Sj/Sgren's syndrome antibody in 14 patients with MLEL and three with BLEL identified among Alaskan Natives (Eskimos, Aleuts, Indians). It also provides additional follow-up data
Received from the *Arctic InvestigationsLaboratory,Center for Infectious Diseases, Centers for Disease Control, the tAlaska Native MedicalCenter, and the :[:ProvidenceMedicalCenter, Anchorage, Alaska; and the w Stokes,Jr. P,~search Institute, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania. Revision accepted for publication 6 March 1987. Dr. Krishnamurthy's current address is the National Cancer Registry, Tata Memorial Hospital,Parel, Bombay,India. Dr. Dohan'scurrent address is the Universityof the Caribbean, Montserrat, West Indies. This work was supported in part by InteragencyAgreement YOI-CP-00500 between the Centers for Disease Control and the National Cancer Institute. Address correspondence and reprint requests to Dr. Lanier: Arctic InvestigationsLaboratory,Centers for Disease Control, 22.5 Eagle Street, Anchorage, AK 99.501. 0046-8177/87 $0.00 + .2.5 986
on the eight patients from this population whose cases were originally reported in 1972. 5 MATERIALAND METHODS
Case Selection and Review The Alaskan Native population includes three ethnic groups, Eskimos, Indians, and Aleuts, many of whom live in rural parts o f Alaska. In the 1970 census, 58 per cent of the total Alaskan Native population of 50,819 were Eskimo or Aleut and 32 per cent were I n d i a n . T h e three largest Eskimo subgroups are the Yupik-speaking Eskimo along the southwest coast, the Inupiaq-speaking Eskimo along the north and northwest coasts, and the Sugpiagspeaking Eskimo on the North Pacific rim. Aleuts are thought to be linguistically related to Eskimos and continue to live on the Alaskan peninsula and Aleutian Island chain. Indians include Athabaskan Indians in interior Alaska and Northwest Coast Indian tribes (Tlingit, Haida, Tsimshian) who live along Alaska's southeastern panhandle. Health care is provided by the Indian Health Service, Public H e a h h Service, and native health corporations. Primary and secondary health care to the village is provided through village health clinics and (egional hospitals. Referrals for tertiary care are largely made to the Alaska Native Medical Center in Anchorage. We sought to identify all cases of primary malignant neoplasm o f the salivary gland as well as BLEL diagnosed in Alaskan Natives between 1966 and 1980. Sources surveyed included a population-based registry of cancer in Alaskan Natives; the tumor registry, pathology files, and medical record discharge diagnoses o f the Alaska Native Medical Center, other Indian Health Service facilities, and private hospitals in Alaska; and death certificates. Medical records including clinical, operative, and pathology reports of all patients with a diagnosis of MLEL or BLEL were reviewed in detail. When relevant, information was o b t a i n e d f r o m hospitals outside Alaska. Demographic, clihical, laboratory, therapeutic, and followup data (to December 1982) were abstracted for each patient. Salivary gland cancers were classified according to standard criteria) ~ Neoplasms classified as BLEL or MLEL had histologic features as described in the literature, l'4-1~ All histologic types of primary malignancies arising in the major salivary glands between 1966 and 1980 were included in rate calculations. Population figures were derived from the 1970 census data
SALIVARYGLANDCANCERIN ALASKANNATIVES[Krishnamurthyet al.)
tbr Alaskan Natives32 Two additional patients with MLEL, one who lived outside Alaska at the time of diagnosis and another whose initial tumor was diagnosed in 1960, were excluded from rate calculations but were included in the clinical and pathologic review. T h e numbers of patients in this population who would be expected to develop cancer of the major salivary glands were calculated by applying age- and sex-specific incidence rates for US whites from the T h i r d N a t i o n a l C a n c e r Survey 23 to p o p u l a t i o n figures for Alaskan Natives. Statistical significance of the ratio o f the number of cancers observed (O) to the calculated n u m b e r expected (E) was tested by the method of Bailar and Ederer34 Rates were adjusted to the world standard population35 Pathology reports and all available paraffin-embedded, hematoxylin-eosin-stained sections from all neoplasms were reviewed by three pathologists (SK, PD, JL). Special stains (alcian green, Verhoeff's elastica, reticulin, periodic acid-Schiff, and acid-fast for Mycobacterium tuberculosis) were available in f o u r cases. Although hematoxylin-eosin-stained sections of the primary tumor could not be reviewed in two patients (cases 9 and 10), the original report was available from case 9 and metastatic t u m o r tissue from the other. When available, nonneoplastic salivary gland tissue adjacent to the lesion was reviewed for evidence o f BLEL or other pathologic changes. Immunologic Studies
Serum antibodies to EBV were tested with indirect immunofluorescence36-2s Specifically, IgA and IgG titers to viral capsid antigen, the restricted and diffuse components o f the early antigen complex, and the viral nuclear antigen were determined in 13 patients. EBV DNA in the tumor tissue of two patients was tested by DNA hybridization methods. 29 HLA testing o f blood from six patients was done by the lymphocyte microcytotoxicity method, s~ Sera from 11 patients were tested by the Ouchterlony gel double-immunodiffusion technique and by the direct immunofluorescence method for antibodies characteristic o f a u t o i m m u n e disease. Sera were, tested at several dilutions for Sj6gren's syndrome antibodies A, B, and C (SS-A, -B, -(3) using a whole cell sonicate of Wil-2 cells. 31,32 The sera were also screened for Sm and U 1-ribonucleoprotein antibodies against h u m a n spleen and calf thymus extracts. Antinuclear antibody was studied by indirect immunofluorescence at a 1:30 serum dilution in an HEP-2 tissue culture substrate, s2 RESULTS Epidemiologic, Clinical, a n d M o r p h o l o g i c Studies
During the 15 years from 1966 to 1980, primary major salivary gland cancers were identified in 16 Alaskan Natives living in Alaska. Distribution o f these 16 patients by age and sex and the incidence rates are given in table 1. Five of 16 patients were men, and 11 were women. Average annual incident rates per 100,000 population, adjusted to the world
TABLE 1. Age and Sex Distribution of 16 Alaskan Natives with Primary Major Salivary Gland Cancers*
Age at diagnosis(yr) <30 30-39 40-49 50-59 ~>60 Total Crude ratet Age-adjusted rate~ Observed:expected ratio
Men
Women
1 0 1 2 1 5 1.17 1.73 1.7
1 5 2 3 0 I1 2.63 3.31 4.7w
* Excludes two native women,one diagnosed in 1960 and another diagnosed while residing outside Alaska. t Incidencerate per 105 population based on 1973 projections from the 1970 census data. :~Adjusted to the world standard population35 wP < 0.05. standard population, were 1.73 in men and 3.31 in women. Alaskan native women had nearly five times the risk o f developing salivary gland cancer as white women in the United States (observed:expected ratio, 4.7; P < 0.05). The observed:expected ratio in men was 1.7, wlfich is not statistically significant. Eleven o f the 16 patients were Eskimo and five were Indian. Twelve of the 16 primary salivary gland malignancies were diagnosed as MLEL, two as adenoid cystic carcinoma, one as an adenocarcinoma (unspecified), and one as a low-grade mucoepidermoid carcinoma. Two other patients with MLEL, one diagnosed prior to 1966 and anotber a nonresident of Alaska at the time of diagnosis, were excluded from rate calculations but included in the clinical and morphologic review (table 2). Nine of tile patients with MLEL were Eskimo and three were Athabaskan Indian. T h e Eskimo patients were almost equally divided a m o n g Yupik-speaking (five) and Inupiaqspeaking (four) Eskimo linguistic groups. Women p r e d o m i n a t e d a m o n g both Eskimo (male:female ratio, 3:6) and Athabaskan I n d i a n (male:female ratio, 0:3) groups. The median age at diagnosis of MLEL was 44 years in men and 36 years in women. T h e r e was no apparent regional clustering o f patients by birthplace or residence at diagnosis. None of the patients were first-degree relatives. T h e diagnosis of BLEL was made in three patients (one Aleut, two Tlingit Indian) during the period 1966-1980. Because surveillance and registration o f benign tumors was not as complete as those for malignant lesions, this may be an underestimate. T h e t h r e e patients with benign lesions are alive without recurrence of tumor seven to 13 years after superficial parotidectomy. Two have rheumatoid arthritis. All neoplasms involved the parotid gland except in three patients (table 2). Histologic features of the lymphoepithelial lesions suggested the n e o p l a s m s were in a continuum from benign lesions at one end to high-grade malignant tumors at the other, with low-grade MLEL in between (table 3). Eight patients had high-grade malignant tumors. T h e original neo987
HUMAN PATHOLOGY
Volume 18, No, 10 (October '1987}
TABLE 2.
Clinical and Morphologic Data on Alaskan
Year of Diagnosis
Age at Diagnosis(yr)
Sex
Ethnicity*
1969 1972 1975
46 33 42
F M M
Indian(Tl) Indian(Tl) Aleut
3 mo, slowly enlarging 3 wk, painless, enlarging 1 yr, slowly enlarging
1977 1971 1969 1969 1970
17 35 52 39 32
F F F F F
Eskimo(Y) Eskimo(Y) Eskimo(In) Eskimo(Y) Indian(Ath)
2 yr, painless 1 yr, painless, slowly enlarging 1 mo, tender, fixed Incidental finding 1 yr, varying size, slightly tender
1960
49
F
Eskimo(Y)
Gradually increasing, painless
1969
47
M
Eskimo(Y)
ll 12
1968 1969
30 26
F M
Indian(Ath) Eskimo(In)
Incidental finding, hard, slightly tender 6 too, tender, rock hard 2 mo, VII nerve involvement
13
1971
31
F
Eskimo(In)
14 15 16tt 17
1974 1976 1973 1980
44 44 29 58
F F F M
Eskimo(In) Indian(Ath) Eskimo(Y) Eskimo(Y)
4 yr, increasing; 6 mo, painless, fixed 5 mo, mass 1 yr, slowlyenlarging, painful Lump behind ear 6 too, slowlyenlarging, painful, hard
1968 1970 1972 1975
70 50 56 59
M F M F
Eskimo(In) Eskimo(In) Indian(Ath) Indian(Ath)
Enlarging mass Unknown Mass Massfor )-ears; recently enlarging, painful, tender
Case Benign iymphoepithelial lesions 1 2 3 Malignant lymphoepithelial lesions, low-grade 4 5 6 7 8 9tt Malignant lymphoepithelial lesions, high-grade 10
Other carcinomas 18 19 20 21
Duration and Clinical Characteristicst
* Subgroups are identified in parentheses: for Indians, Tlingit (TI) and Athabaskan (Ath); for Eskimos, Inupiat (In) and Yupik (Y). t All tumors involved tile parotid gland except in cases 1, 14, and 17. ~tLocal indicates tumor confined to gland; regional, gland and regional lymph nodes involved; distant, distant organ involvement. wTumor size based on clinical, not pathologic, examination is indicated in parentheses. 82H, hemimandibulectomy. ** To December 1982. [t Excluded from rate calculations. plasm was usually unifocal a n d infiltrated the surr o u n d i n g salivary gland (fig. 1A). Germinal centers were not observed in the l y m p h o i d c o m p o n e n t . Malignant cells were in disorderly sheets, trabeculae, or poorly d e f i n e d islands (fig. 1B). O v e r l a p p i n g o f cells f o r m e d syncytia with obscured cytoplasmic outlines (figs. 1B and C). Cellular p l e o m o r p h i s m o f polygonal o r spindle-shaped cells was observed (figs. 1B, 1C, a n d 1D). Nuclear chromatin was coarse o r c l u m p e d (Figs. 1C inset and 1D). F r e q u e n t mitoses a n d p r o m i n e n t , often nmltiple and p l e o m o r p h i c nucleoli were present. Anaplasia was r a r e a n d o n l y n o t e d in foci. Necrosis, s q u a m o u s metaplasia, and crush artifact were each observed in two patients. Fibroplasia was also observed. Carcinoma metastatic to l y m p h nodes had cellular detail similar to that o f the original t u m o r . Atypical and hyperplastic salivary ducts were n o t e d in the islands o f malignant cells. T h e ducts o f the s u r r o u n d i n g n o n n e o p l a s t i c salivary gland demonstrated atypical epithelial changes a n d l y m p h o i d cell infiltrates. T h e eight patients with high-grade M L E L died f r o m their neoplasm o r related complications eight 988
m o n t h s to five years a f t e r t r e a t m e n t (table 2). Prim a r y t h e r a p y included gland resection alone in o n e patient, g l a n d a n d radical neck dissection in five, gland resection a n d r a d i o t h e r a p y in one, and radiation alone in one. At diagnosis, extension o f disease into r e g i o n a l n o d e s was d o c u m e n t e d in six o f the eight patients; in two, staging was u n k n o w n . In o n e (case 10), the t u m o r was f o u n d incidentally o n physical e x a m i n a t i o n ; in cases 11 a n d 12, cervical l y m p h nodes were clinically negative, a l t h o u g h metastatic t u m o r was histologically d e m o n s t r a t e d in single l y m p h nodes in the dissected neck specimen. T h r e e patients h a d involvement o f only o n e l y m p h n o d e at initial histologic diagnosis. In these eight patients with h i g h - g r a d e MLEL, metastases subsequently developed in l y m p h nodes, liver, lungs, bones, and skin. T h e six patients whose tumors were classified as low-grade M L E L a p p e a r e d to have some m o r p h o logic features o f both benign and malignant lesions. T h e lesions were usually circumscribed but n o n e n capsulated, with areas o f infiltration into the surr o u n d i n g salivary gland. In contrast to the benign variant, the epithelial cell proliferation in low-grade M L E L was m o r e p r o n o u n c e d and d i s o r d e r l y , a n d
SALIVARYGLAND CANCERIN ALASKANNATIVES[Krishnamurthy et al,) Natives with Salivary Gland Neoplasms, 1966-1980 Initial Diagnosis and Treatment Extent ( n o d e s positive)*
T u m o r sizew (cm)
Follow-up**
Salivary Gland Surgery
Radical Neck Dissections~
Radiation
Recurrence
Metastases
Outcome (yr)
Tumor at Follow-up
Local Local Local
2 x 1.5 x 1 2 (clin) 3 x 2 (clin)
Excision Superficial Superficial
-
m
-
-
Alive (13) Alive (10) Alive (7)
-
Local Local Local Local Local
2.8 4 x 3 x 2 (clin) 1.6 2.5 1.8
+ +
m
-
-
Alive Alive Alive Alive Alive
(5) (11) (13) (13) (12)
-
Local
0.8
Superficial Superficial Superficial Superficial Superficial + deep Excision
-
+(x2)
-
Alive (22)
-
Unknown
1.8
Superficial
(Refused)
+
+
Dead (<1)
+
Regional Regional (1)
2 x 3 (clin) 1.8
+(H) +(H)
+
+ +
Dead (3) Dead (1)
+ +
Regional (26)
4 (clin)
Superficial Subtotal + total Total
+
+
Dead (2)
+
Regional (1) Regional Unknown Distant
2.2 4 (clin)
+ +
+ + + +
Dead Dead Dead Dead
(4) (5) (3) (<1)
+ + + +
Local Regional Local Regional
Unknown 2 Unknown
+ +
+ + +
Alive Dead Dead Dead
(7) (I) (7) (<1)
+ + +
7 x 6 x 4 (clin)
B
-
+
Total Total Total None
+ + ? -
+ + +
Total Total Total Total
+ (Refused) -
+ -
D
-
areas s h o w e d indistinct c y t o p l a s m s w h i c h i m p a r t e d a syncytial cellular a p p e a r a n c e . Cells w e r e usually in s h a r p l y d e f i n e d islands b u t s o m e t i m e s o c c u r r e d in sheets o r t r a b e c u l a e (figs. 2 A a n d 2B). T h e islands h a d v a r y i n g d e g r e e s o f p e r i p h e r a l p a l i s a d i n g (fig. ' 2C). N u c l e o l i w e r e p r o m i n e n t , usually single, eosinophilic, a n d u n i f o r m (fig. 2D). N u c l e a r c h r o m a t i n was v e s i c u l a r (fig. 2D). Mitoses w e r e r e a d i l y o b s e r v e d . Necrosis and anaplasia were not seen. The background lymphocytic infiltrate frequently included g e r m i n a l c e n t e r s . A b s e n c e o f l y m p h a t i c sinuses a n d fibrous trabeculae confirmed that these were not l y m p h n o d e s . D u c t o c e n t r i c l y m p h o i d cell a g g r e g a t e s a n d associated d u c t epithelial h y p e r p l a s i a a n d atypia w e r e m o r e p r o n o u n c e d in a d j a c e n t salivary g l a n d tissue t h a n in t h e g l a n d s o f patients with h i g h - g r a d e M L E L (fig. 3). T h e six p a t i e n t s with l o w - g r a d e M L E L a r e alive five to 22 y e a r s a f t e r diagnosis. N o n e o f t h e patients h a v e d e v e l o p e d metastases. T r e a t m e n t consisted o f g l a n d excision with o r w i t h o u t radical n e c k dissection (in two a n d f o u r patients, respectively). N o n e o f t h e patients r e c e i v e d i r r a d i a t i o n . A t diagnosis, t h e n e o p l a s m s h a d n o t e x t e n d e d b e y o n d t h e salivary g l a n d . Local r e c u r r e n c e a n d infiltration o f t u m o r d e v e l o p e d in case 9, b u t n o metastases h a v e d e v e l o p e d by 13 y e a r s a f t e r excision o f t h e s e c o n d r e c u r r e n c e . T h e o r i g i n a l a n d review m o r p h o l o g i c d i a g n o s e s w e r e c o m p a r e d . T h e r e was close a g r e e m e n t f o r B L E L a n d h i g h - g r a d e M L E L . H o w e v e r , as s h o w n in
-
-
table 4, t h e cases classified as l o w - g r a d e M L E L in this r e p o r t (cases 4 to 9) w e r e o r i g i n a l l y d i a g n o s e d as B L E L , B L E L with a t y p i a , l y m p h o e p i t h e l i a l lesion with focal anaplasia, p o o r l y d i f f e r e n t i a t e d c a r c i n o m a , and MLEL. P r e s e n t i n g s y m p t o m s a n d signs did n o t h e l p to d i f f e r e n t i a t e t h e t h r e e g r o u p s o f p a t i e n t s with lymp h o e p i t h e l i a l lesions. H o w e v e r , a h i s t o r y o f increase a n d d e c r e a s e in the size o f t h e lesion was d e s c r i b e d o n l y in p a t i e n t s with l o w - g r a d e M L E L . I n addition, a l t h o u g h h a r d n e s s o f t h e lesion was m e n t i o n e d in o n l y t h r e e o f t h e six patients with h i g h - g r a d e malign a n t lesions, it was n o t d e s c r i b e d in any, with b e n i g n o r l o w - g r a d e m a l i g n a n t t u m o r s (table 2). T w o o f t h r e e p a t i e n t s with B L E L (cases 2 a n d 3) h a v e develo p e d r h e u m a t o i d arthritis, w h e r e a s o n l y o n e o f the 14 p a t i e n t s with M L E L (case 7 with l o w - g r a d e M L E L ) has b e e n d i a g n o s e d with r h e u m a t o i d arthritis.
Immunologic Studies
Epstein-Barr Virus T e s t i n g f o r E B V a n t i b o d y was d o n e o n at least o n e s e r u m s a m p l e f r o m 13 d i f f e r e n t patients (table 5). S a m p l e s w e r e o b t a i n e d at d i a g n o s i s f r o m o n l y two patients (cases 4 a n d 17). E x c e p t f o r a n I g A a n t i viral c a p s i d a n t i g e n titer o f 1:10 in case 4 a n d a n I g G a n t i - e a r l y a n t i g e n (diffuse) titer o f 1:10 in case 17, the E B V titers w e r e n o t u n u s u a l f o r this p o p u l a t i o n a n d i n d i c a t e d past p r i m a r y E B V infection. 9
8
9
HUMAN PATHOLOGY
Volume 18, No. 10 (October 1987] TABLE 3.
Nonneoplastic Salivary Gland
Lymphoid Component
Neoplastic Component Islands, Sheets, Trabeculae
Lymphocytic Infiltrates
Germinal Centers
+++ + +
+++ +++ +++
++ +++
Islands Islands
Orderly Orderly
+ +
+
+
+
Islands
-
5
+
++
Islands
6
+
+
Islands
Orderly
+
7
+
+ Ductocentric + Ductocentric +
Orderly and disorderly Orderly
-
Disorderly
-
8
+
+
++
Islands, sheets, trabeculae Islands, sheets
Disorderly
•
+ +
+ +
+ -
Disorderly Disorderly
12 13
+ +
+ +
-
14 15 16
+ ++ +
+ ++ -
-
Islands, sheets Islands, sheets, trabeculae ND Sheets, trabeculae Islands, sheets Islands, sheets Sheets
Disorderly Disorderly Disorderly
17
ND
ND
ND
Sheets
Disorderly
Case Benign lymphoepithelial lesions 1" 2 3 Malignant lymphoepithelial lesions, low-grade 4
9t Malignant lymphoepithelial lesions, high-grade 10 11
Duct Hyperplasia
Histologic Features of SaIivary Grand
Orderly/ Disorderly
Disorderly Disorderly
Peripheral Palisading
++
F
ABBREVIATION:ND, not determined; material unsatisfactory or sampling insufficient. * Entire gland consisted of diffuse lymphocytic infiltrates with prominent areas of duct hyperptasia. No clearly identifiable neoplasm. "["Original material was not reviewed; it was reported as "benign lymphoepithelial lesion with foci of anaplasia." Single lymph node examined; no evidence of malignancy. S e r u m for EBV a n t i b o d y testing was o b t a i n e d at the t i m e o f r e c u r r e n t o r metastatic disease f r o m f o u r p a t i e n t s (cases 13, 14, 15, a n d 17). T w o p a t i e n t s (cases 14 a n d 17) s h o w e d an i n c r e a s e in n e a r l y all E B V antibodies with d e v e l o p m e n t o f distant metastases. H o w e v e r , o n e p a t i e n t (case 15) who d e v e l o p e d extensive metastatic disease a n d two (cases 13 a n d 14) with metastases involving only cervical l y m p h n o d e s did not show m a r k e d l y elevated EBV a n t i b o d y titers. T i t e r s w e r e w i t h i n n o r m a l limits in t h e r e m a i n i n g patients e x c e p t f o r two (cases 5 a n d 9). Six a n d f o u r s a m p l e s w e r e tested f r o m these two patients, respectively, a l t h o u g h results o f only the earliest a n d latest s e r u m s a m p l e s are listed in table 5. T h e s e two p a t i e n t s a r e alive a n d w i t h o u t t u m o r . S e r u m was o b t a i n e d f o r E B V testing at least f o u r years a f t e r s u r g e r y a n d s h o w e d persistently elevated I g A anti--viral capsid a n t i g e n a n d I g G a n t i - e a r l y antigen (restricted) titers, a n d in o n e patient a n t i - e a r l y a n t i g e n (diffuse) as well. Tests f o r EBV m a r k e r s in tissue were d o n e on two patients (cases 4 a n d 17). EBV D N A hybridization was positive in t u m o r tissue f r o m b o t h patients, while t o u c h p r e p a r a t i o n s f o r the viral n u c l e a r antigen w e r e positive only in case 17.
Human Leukocyte Antigen Results o f H L A typing studies a r e s h o w n in table 6. Six patients w e r e t y p e d mainly f o r loci A a n d B. N o p e r s o n s t y p e d w e r e B8. O n l y o n e p e r s o n was tested for D R antigens a n d he was f o u n d to be DRw4. T h i s patient h a d n o evidence o f r h e u m a t o i d arthritis o r related d i s o r d e r s .
Autoimmune Antibodies Results o f serologic tests for a u t o i m m u n e antibodies are s h o w n in table 7. Sj6gren's s y n d r o m e antibodies A a n d B (SS-A, -B) were not d e t e c t e d in a n y o f the 11 sera tested. SS-C or r h e u m a t o i d a n t i n u c l e a r antibody (reactive against extracts from EBV-infected B cells a n d t h o u g h t to be E p s t e i n - B a r r n u c l e a r antigen; C. Peebles, personal c o m m u n i c a t i o n , 1984) was identified in t h r e e patients, two o f w h o m h a d or d e v e l o p e d r h e u m a t o i d arthritis. Clinically significant titers o r a n t i n u c l e a r a n t i b o d y were not f o u n d by indir e c t i m m u n o f l u o r e s c e n c e in t h e I 0 p a t i e n t s with M L E L . T h e low titers o b s e r v e d in six o f these 10 patients were also f o u n d in sera tested at the s a m e time f r o m f o u r o f n i n e Alaskan Natives without salivary l y m p h o e p i t h e l i a l lesions. T h e only high titer was in 990
SALIVARYGLAND CANCER IN ALASKANNATIVES(Krishnamurthyet al.) Lymphoepithelial Lesions in Alaskan Natives Neoplastic Component
Sync)'tial/ Discrete
Pleomorphism
Nuclear Chromatin
! ncreased Nuclear-Q'toplasmic Ratio
Mitoses
Necrosis
m
m
-
ND Vesicular
. .
Syncytial and discrete Discrete
-
Vesicular
•
+
-
+
-
Vesicular
-
+
-
+
Syncytial and discrete
+
Vesicular
+
+
-
+ +
Syncytial and discrete Syncytial and discrete
•
Vesicular, coarse Vesicular, coarse
+
+
-
-
+
+
-
+
Syncytial Syncytial and discrete Syncytial Syncytial, crush Syncytial Syncytial Syncytial and discrete Syncytial
+ +
ND Coarse
+ +
+ +
+
+ +
+
+ +
Coarse Coarse
+ +
+ + + +
-
+ + (pleomorphic)
ND ND
+ + +-
Coarse Coarse Coarse, clumped Coarse
+ + •
+ + +
-
-
+
•
-
+ (pleomorphic) + (pleomorphic) + (pleomorphic, prominent) +
•
. .
Nucleolus
Discrete Discrete
•
. .
Anaplasia
Metastases or Infiltration
one patient with BLEL who also had rheumatoid arthritis. Antibody reactive to h u m a n spleen or calf thymus extracts was not detected in any of the 11 patients, except in one with a high-grade MLEL who had antibody to human spleen extract only. DISCUSSION
T h e data presented in this article support previous findings that Alaskan Natives, particularly w o m e n , are at increased risk for salivary gland cancer and that a large proportion (75 per cent) of the major salivary gland cancers are malignant lymphoepithelial lesions (MLEL). 2,s O f interest is that three patients with MLEL were Athabaskan Indian, not Eskimo. To date, there are no published reports of cases of MLEL in North American Indians outside Alaska, and data on salivary gland cancer among Indians in New Mexico and Arizona show no evidence of an excess risk. s2 Histologic, clinical, and follow-up findings from the patients reported in this article support the possibility of a spectrum of salivary lymphoepithelial lesions. In particular, a low-grade malignant lesion that does not metastasize but may recur locally appears to exist, a l t h o u g h it c a n n o t be d e t e r m i n e d clearly whether the favorable outcome of this group of patients was a result of early intervention or the in991
. .
+ + +
Unknown + + + + + - :[: +
herent nature of the lesion. Surgical treatment including gland resection and neck dissection without radiotherapy may suffice for this group of patients. On the other hand, gland resection and neck dissection, even in those who had only a single node involved at the time of diagnosis, did not prevent subsequent metastases and death. T h e major histoiogic features distinguishing low-grade MLEL include prominent but uniform nucleoli in the neoplastic cells; well-defined islands or sheets of cells; peripheral palisading; absence of necrosis and anaplasia; vesicular nuclear chromatin; and a lymphoid background that usually contains germinal centers. Duct epithelial hyperplasia, atypia, and lymphoid infiltrates, frequently ductocentric, are seen in the adjacent salivary gland. Metastases are not found. T h e background lymphoid infiltrate may also show a s p e c t r u m o f appearances, although in all three neoplastic groups that infiltrate was composed o f niature, well-differentiated, polymorphic lymphoid cells. In benign l y m p h o e p i t h e l i a l lesions (BLEL), the infiltrates were in multifocal aggregates that often showed germinal centers or in diffuse sheets extending throughout the salivary gland. The lymphoid infiltrates in low-grade MLEL were generally confined to the tumor. Germinal centers were present in some tumors. In high-grade MLEL, ger-
HUMAN PATHOLOGY
Volume l& No. 10 (October 1987)
FIGURE t. High-grade malignant lymphoepithelial lesion. A, Case 14. Neoplasm infiltrating salivary gland. B, Case 16. Syncytial arrangement of neoplastic cells obscuring cytoplasmic outlines. C, Case 12. Metastatic carcinoma In lymph node. Inset, Note coarse chromatin, syncyHal arrangement of neoplastic cells. D, Case 14. Spindle-shaped neoplastic cells with coarse chromatin. (Aft, hematoxylin-eosin stain. Original magnification: A, x 20; Band C, x50; insetand D, x125.]
992
SALIVARYGLAND CANCER IN ALASKANNATIVES(Krishnamurthy et al.)
FIGURE 2. Low-grade malignant lymphoepithelial lesion. A, Case 4. Sharply defined epithelial islands of neoplasiic cells in lymphocytic background. B, Case 5. Islands of neoplastic cells in lymphocytic background. C, Case 5. Peripheral paUsading. D, Case 8. Sharply defined cell islands, with prominent nucleoli and vesicular chromatin in neoplastic cells. (A//,hematoxylin-eosin stain. Original magnification: Aand D, x 125; B, x 100; C, x 200.)
993
HUMAN PATHOLOGY
Volume 18, No. 10 (October '1987)
FIGURE 3. Low-grade malignant
lymphoepithelial lesion. Case 8. Hyperplastic duct in nonneoplastic gland. (Hematoxylin-eosin stain. x `125.]
minal centers were not observed and the infiltrate was so dense as to suggest lymphoma. Although two patients in this series appeared to have had Epstein-Barr virus (EBV)-positive neoplasms as based on EBV DNA hybridization and viral nuclear antigen studies, serologic results at diagnosis were not typical of EBV-associated tumors. As has been described in patients with nasopharyngeal carcinoma, increases in EBV antibody titers were documented in two patients with MLEL who developed metastases. In two other patients, who did not develop recurrent tumors or metastases, persistently elevated EBV antibody titers were present. T h e reason for these antibody patterns are not clear at this time. Initial and Review Histologic Diagnoses in Cases of Low-grade Malignant Lymphoepithelial Lesions
TABLE 4.
Case 4 5 6 7 8 9
Initial Diagnosis*
ReviewDiagnosis
BLEL(2); LEL,NOS (1); BLELwith MLEL,low-grade atypia (1) BLEL(2); MLEL(1); anaplasticLEL MLEL,low-grade (2) BLEL(2); BLELwith mitosesand MLEL,low-grade atypia (1) BLEL(1); squamouscell carcinoma MLEL,low-grade with lymphoepithelialareas (1); MLEL(1) MLEL,low-grade Poorly differentiatedsquamouscelt carcinoma (1); MLEL(I) BLEL(1); LEL with focalanaplasia Original material (1); Mikulicz'sdisease (1); poorly not reviewed differentiatedcarcinoma(2)
ABBREVIATIONS:BLEL,benign lymphoepitheliallesion, LEL, lymphoepithelial lesion; MLEL, malignant Iymphoepitheliallesion; NOS, not otherwisespecified. * Numbers in parentheses indicatethe number of pathologists making the diagnosis. 994
Benign lymphoepithelial lesion may occur alone or in association with Sj6gren's syndromeJ ~-14 Although patients with Sj63gren's syndrome are at increased risk for cancer, 3 the malignancies that develop mainly arise in l y m p h o i d , not epithelial, cells, l~ MLEL is an undifferentiated or poorly differentiated carcinoma that is frequently fatalJ ,5-x~ These tumors have not been associated with SjOgren's syndrome or other autoimmune phenomena. In this series, two of the three patients with benign lesions had rheumatoid arthritis, and one with lowgrade malignant lesions developed rheumatoid arthritis five years after resection of her neoplasm. No other patient with MLEL had Sjrgren's syndrome, arthritis, or related disorders. In primary Sjrgren's syndrome, SS-A and -B an- 9 tibodies are found, whereas SS-C and anti-salivary gland antibodies are n o t J 3 In contrast, the absence of SS-A and -B antibodies but the presence of SS-C and anti-salivary gland antibody characterize secondary Sj6gren's s y n d r o m e with r h e u m a t o i d arthritis, ss BLEL is a feature of Sjrgren's syndrome. 12,1~,sl,s3 Serologic tests in 1 1 patients were negative for antibodies frequently found in Sj6gren's syndrome and other autoimmune diseases, despite the fact that histologic findings were similar to those found in BLEL and Sjrgren's syndrome. T h e term malignant lymphoepithelial lesion was used originally because some patients with neoplasms that had many features o f BLEL were observed to have a fatal outcome. 6 T h e difficulty in determining the original diagnosis in some patients in the current series (table 4) a n d the clinical and morphologic findings on review suggest that the benign and malignant lesions represent poles of a spectrum and may evolve from the same disease process. Unanswered questions remain. Should MLEL be
SALIVARYGLAND CANCERIN ALASKANNATIVES[Krishnamurthy et al.) TABLE 5.
Epstein-Barr Virus Antibody Titer in Alaska Natives with Lymphoepithelial Lesions of the Salivary Glands
Case Benign lymphoepithelial lesion 1 2 3 Malignant lymphoepithelial lesion, low-grade 4
Date of Diagnosis
Date of Sample
2/69 3/72 1/75
08/75 05/72 05/82
6/77
06/77 12183 08175 01/79 04172 09/79 03/72 03/79 08/75
5
3171
6
3/69
7
5/69
8
1/70
Clinical Findings
IgA VCA
IgG VCA
IgA EA-D
Localized Localized Localized
<10 <10 <10
80 80 640
<'1~) <10
Localized
10 <10 40 40 < 10 <10 <10 <10 <10
320 160 320 1280 160 160 160 80 80
Localized Localized Localized Localized
03/83
9
6/60
Malignant lymphoepithelial lesion, high-grade 13 14 15 17
7171 5/74 11/76 8/80
<10
80
08/75 08/83
(Recurrences in 1964, 1969)
<10 80
320 640
04/72 08177 10/78 03/82 08/80 01/81
Nodes Nodes Metastases Metastases
<10 <10 10 <10 <10 40
80 160 640 320 320 640
Metastases
IgG EA-D (R) <10
<10 <10 ~:'1() <'1~) <10 <10
<'1() ... ... <'1() <10 <10
EBNA
40 160 80
<10 <10 20 10 (80) < 10 <10 <10
320 160 80 80 80 80 40 160 20
.
<10
40
<10 <10 (80)
80 80
<10 <10 80 10 I0 40
160 40 80 40 40 40
ABBREVIATIONS:VCA, viral capsid antigen; EA, early antigen; D, diffuse component; R, restricted component; EBNA, Epstein-Barr nuclear antigen.
classified separately or simply g r o u p e d with other anaplastic carcinomas? Do some forms of MLEL have a biologically less malignant course? What is the relationship, if any, between BLEL and MLEL? Is there a common factor between MLEL and nasopharyngeal carcinoma in view of their histologic similarity and reported joint occurrence in both Eskimo and Chinese populations? What is the role of EBV in these lesions? Some o f these questions could b e a d d r e s s e d by the following studies: standardized review of all cases of MLEL reported to date; review of salivary gland cancers outside the circumpolar region and especially in areas at high risk for nasopharyngeal carcinoma; and detailed clinical, morphologic, viral, and a u t o i m m u n e antibody studies o f newly diagnosed cases. In summary, our study substantiates previous findings o f an increased risk in Alaskan Native
w o m e n f o r salivary gland cancer. Most o f these cancers were MLEL or undifferentiated carcinoma. A group o f patients were identified whose neoplasms were diagnosed as low-grade malignancy and did not metastasize, although one of these tumors recurred locally. Clinical and morphological features of this group were intermediate between BLEL and metastasizing, high-grade MLEL. Abnormal EBV titers were found in five of 12 patients, and EBV DNA was identified in the tumor tissue of two patients. SS-A and -B antibodies were not detected in any of 11 patients tested, including 10 with MLEL. T h e small number o f patients in whom these observations were made precludes firm conclusions: A study of all case material available internationally may help shed light on this unique neoplasm.
Acknowledgments. T h e authors t h a n k E. M. T a n , MD, PhD, a n d Carol Peebles, Scripps Clinic a n d Research Center, LaJolla, California, for testing for Sj6gren's synd r o m e a n d other a u t o i m m u n e antibodies.
TABLE 6.
Human Leukocyte Antigens in Alaskan Natives with Salivary Gland Lymphoepithelial Lesions
HLA Loci and Antigen Case
a
I
2,24
7,27
5 7
2,24 2
27 27,40
8 9 17
B
2,24 35,40 1 1 , 2 4 5,15 24,28 27,61
C
DR
2,4 4
Clinical Findings
Pathologic Diagnosis
REFERENCES 1. Nielsen NH, Mikkelsen F, Hansen JP: Incidence of salivary gland neoplasms in Greenland with special reference to an anaplastic carcinoma. Acta Pathol Microbiol 8cand [A] 86:185, 1978 2. Lanier AP, Bender TR, Blot WJ, et al: Cancer incidence in Alaska natives. IntJ Cancer 18:409, 1976 3. Lanier AP, Bender TR, Blot WJ, et al: Cancer in Alaskan natives: 1974-78. Natl Cancer Inst Monogr 62:79, 1982 4. Wallace AC, MacDougall JT, Hildes JA, et al: Salivary gland tumors in Canadian Eskimos. Cancer 16:1338, 1963 5. Arthaud JB. Anaplastic parotid carcinoma ("malignant lym-
Rheumatoid BLEL arthritis MLEL, low-grade Rheumatoid MLEL, low-grade arthritis MLEL, low-grade MLEL, low-grade MLEL, high-grade
ABBREVIATIONS: BLEL, benign lymphoepithelial lesion; MLEL, malignant lymphoepithelial lesion.
995
HUMAN PATHOLOGY
Volume 18, No. 10 (October 1987]
TABLE 7, Serum Autoantibodies in Alaskan Natives with Salivary Gland Lymphoeplthelial Lesions SS-Antibodies*t Case Benign lymphoepithelial lesion 382 Malignant lymphoepithelial lesion, low-grade 4 5 6 7 82
8 9 Malignant iymphoepithelial lesion, high-grade 13 14 15 17
Date of Diagnosis
Date of Sample
A
B
c
FANA$
HSE/CTEw
1/75
5/82
-
-
+ (>4)
3+
-
6/77 3171 3/69 5/69 1170 6/60
6/77 8/75 10178 3/72 8/75 8/75
. . -
.
1+
_/-
7/71 5174 11176 8/80
4/72 8/77 12181 8/80
. -
.
. -
.
.
. -
. . -
I +
-
-
-
1+
-
1+ 1+
+/---/-
1+
-
.
+ (4) .
-
.
+ (4)
.
* Titers are reciprocal of highest dilution. t Sj6gren's syndrome (SS) antibodies A, B, and G (or rheumatoid antinuclear antibody, RANA). Antigen source was Wil-2 cell sonicate. Titers ~ 1:4 dilution are considered positive. ~: Indirect fluorescent antinuclear antibody (FANA) using tissue culture human epithelial cell line (HEp-2) substrate and serum at 1 : 3 0 dilution. 1-1 + = low positive; 2 + = moderate positive; ~>3-4 + = strong positive w HSE, human spleen extract; CTE, calf thymus extract. 82Case 3 had rheumatoid arthritis at time of diagnosis of tumor; Case 7 was diagnosed with rheumatoid arthritis in 1974.
6. 7. 8. 9. 10.
11. 12. 13. 14. 15. 16. 17. 18.
19. 20.
phoepithelial lesion") in seven Alaskan natives. Am J Clin Pathol 57:275, 1972 Hilderman WC, Gordon JS, Large HL, et al: Malignant lymphoepithelial lesion with carcinomatous component apparendy arising in parotid gland. Cancer 15:606, 1962 Gravanis MB, Giansanti JS: Malignant histopathologic counterpart o f the benign lymphoepithelial lesion. Cancer 26:1332, 1970 Ferlito A, Donati LF: Malignant lymphoepithelial lesions. J Laryngol Otol 91:869, 1977 Nagao K, Matsuzaki O, Saiga H, et al: A histopathologic study of benign and malignant lymphoepithelial lesions of the parotid gland. Cancer 52:1044, 1983 Thackray AC, Lucas RB: Tumors of the major salivary glands. In Firmingen HI (ed): Atlas of T u m o r Pathology, 2nd series, fascicle 10. Washington, DC, Armed Forces Institute of Pathology, 1974 Dong H, Lo G: Malignant lymphoepithelial lesions of the salivary glands with anaplastic carcinomatous changes. Cancer 52:2245, 1983 Godwin J T : Benign lymphoepithelial lesion of the parotid gland. Cancer 5:1089, 1952 Morgan WS, Castleman B: A clinicopathologic study of "Mikulicz's disease." A m J Pathol 29:471, 1953 Evans RW, Cruikshank AH: Epithelial Tumors of the Salivary Glands. Philadelphia, WB Saunders, 1970 Thackray AC, Sobin LH: Histological typing of salivary gland tumors. In International Histological Classification o f Tumors, no. 7. Geneva, World Health Organization, 1972 Batsakis JG, Gernacki EG, Rice DH, et ah Malignancy and benign lymphoepithelial lesion. Laryngoscope 15:389, 1975 Pinkus GS, Dekker A: Benign lymphoepithelial lesion of the parotid glands associated with reticulin cell sarcoma. Cancer 25:121, 1970 Shanmugarathnam K: Histological typing of nasopharyngeal carcinoma. In De-the GG, Ito Y (eds): Nasopharyngeal Carcinoma: Etiology and Control. IARC scientific publications no. 20. Lyon, International Agency for Research on Cancer, 1978 Henle W, Henle G. Epidemiologic aspects of Epstein-Barr virus (EBV)-associated diseases. Ann NY Acad Sci 354:326, 1980 Lanier AP, Bornkamm GW, Henle W, et al: Association of Epstein-Barr virus with nasopharyngeal carcinoma in
21. 22. 23. 24. 25.
26. 27. 28. 29.
30. 31. 32.
33.
996
Alaskan native patients: serum antibodies and tissue EBNA and DNA. I n t J Cancer 28:301, 1981 Saemundsen AK, Albeck H, Hansen JPH, et al: Epstein-Barr virus in nasopharyngeal and salivary gland carcinomas of Greenland Eskimos. B r J Cancer 46:721, 1982 1970 Census of Population, vol I, pt 3. Washington, DC, Bureau o f the Census, US Department of Commerce, I973, pp 205 Cutler SJ, Young J L J r (eds): Third National Cancer Survey: Incidence Data. Washington, DC, National Cancer Institute, 1975 Bailar JC III, Ederer F: Significance factors for the ratio of a Poisson variable to its expectations. Biometrics 202:639, 1964 Waterhouse J, Muir C, Correa P, et al (eds): Cancer Incidence in Five Continents, vol III. IARC Scientific Publications no. 15. Lyon, International Agency for Research on Cancer, 1976 Henle G, Henle W: Epstein-Barr-virus-specific IgA serum antibodies as an outstanding feature of nasopharyngeal carcinoma. I n t J Cancer 17:1, 1976 Henle G, Henle W, Horowitz CA: Antibodies to Epstein-Barrvirus-associated nuclear antigen in infectious mononucleosis. J Infect Dis 130:231, 1974 Henle W, Henle G, Horowitz CA: Epstein-Barr virus-specific diagnostic tests in infectious mononucleosis. HUM PATHOL 5:551, 1974 Bornkamm GW, Stein H, Lennert K, et al: Attempts tO demonstrate virus-specific sequences in human tumors: IV. EB viral DNA in European Burkitt lymphoma and immunoblastic lymphadenopathy with excessive plasmacytosis. I n t J Cancer 17:177, 1976 Terasaki PI, Bernoco D, Parks MS, et al: Microdroplet testing for HLA-A, -B, -C, and -D antigens. Am J Clin Pathol 69:103, 1978 Alspaugh M, Tan EM: Antibodies to cellular antigens in Sjogren's syndrome. J Clin Invest 55:1067, 1975 Y o u n g J L J r , Percy CL, Asire AJ (eds): Surveillance, epidemiology, and end results: incidence and mortality data, 1973-1977. N I H publication no. 81-2330. Natl Cancer Inst Monogr 57:122, 1981 Moutsopoulos HM, Chased TM, Mann DL, et al: Sjogren's syndrome (sicca syndrome): current issues. Ann Intern Med 92(2 pt 1):212, 1980
Received from the *Arctic InvestigationsLaboratory,Center for Infectious Diseases, Centers for Disease Control, the tAlaska Native MedicalCenter, and the :[:ProvidenceMedicalCenter, Anchorage, Alaska; and the w Stokes,Jr. P,~search Institute, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania. Revision accepted for publication 6 March 1987. Dr. Krishnamurthy's current address is the National Cancer Registry, Tata Memorial Hospital,Parel, Bombay,India. Dr. Dohan'scurrent address is the Universityof the Caribbean, Montserrat, West Indies. This work was supported in part by InteragencyAgreement YOI-CP-00500 between the Centers for Disease Control and the National Cancer Institute. Address correspondence and reprint requests to Dr. Lanier: Arctic InvestigationsLaboratory,Centers for Disease Control, 22.5 Eagle Street, Anchorage, AK 99.501. 0046-8177/87 $0.00 + .2.5 986
on the eight patients from this population whose cases were originally reported in 1972. 5 MATERIALAND METHODS
Case Selection and Review The Alaskan Native population includes three ethnic groups, Eskimos, Indians, and Aleuts, many of whom live in rural parts o f Alaska. In the 1970 census, 58 per cent of the total Alaskan Native population of 50,819 were Eskimo or Aleut and 32 per cent were I n d i a n . T h e three largest Eskimo subgroups are the Yupik-speaking Eskimo along the southwest coast, the Inupiaq-speaking Eskimo along the north and northwest coasts, and the Sugpiagspeaking Eskimo on the North Pacific rim. Aleuts are thought to be linguistically related to Eskimos and continue to live on the Alaskan peninsula and Aleutian Island chain. Indians include Athabaskan Indians in interior Alaska and Northwest Coast Indian tribes (Tlingit, Haida, Tsimshian) who live along Alaska's southeastern panhandle. Health care is provided by the Indian Health Service, Public H e a h h Service, and native health corporations. Primary and secondary health care to the village is provided through village health clinics and (egional hospitals. Referrals for tertiary care are largely made to the Alaska Native Medical Center in Anchorage. We sought to identify all cases of primary malignant neoplasm o f the salivary gland as well as BLEL diagnosed in Alaskan Natives between 1966 and 1980. Sources surveyed included a population-based registry of cancer in Alaskan Natives; the tumor registry, pathology files, and medical record discharge diagnoses o f the Alaska Native Medical Center, other Indian Health Service facilities, and private hospitals in Alaska; and death certificates. Medical records including clinical, operative, and pathology reports of all patients with a diagnosis of MLEL or BLEL were reviewed in detail. When relevant, information was o b t a i n e d f r o m hospitals outside Alaska. Demographic, clihical, laboratory, therapeutic, and followup data (to December 1982) were abstracted for each patient. Salivary gland cancers were classified according to standard criteria) ~ Neoplasms classified as BLEL or MLEL had histologic features as described in the literature, l'4-1~ All histologic types of primary malignancies arising in the major salivary glands between 1966 and 1980 were included in rate calculations. Population figures were derived from the 1970 census data
SALIVARYGLANDCANCERIN ALASKANNATIVES[Krishnamurthyet al.)
tbr Alaskan Natives32 Two additional patients with MLEL, one who lived outside Alaska at the time of diagnosis and another whose initial tumor was diagnosed in 1960, were excluded from rate calculations but were included in the clinical and pathologic review. T h e numbers of patients in this population who would be expected to develop cancer of the major salivary glands were calculated by applying age- and sex-specific incidence rates for US whites from the T h i r d N a t i o n a l C a n c e r Survey 23 to p o p u l a t i o n figures for Alaskan Natives. Statistical significance of the ratio o f the number of cancers observed (O) to the calculated n u m b e r expected (E) was tested by the method of Bailar and Ederer34 Rates were adjusted to the world standard population35 Pathology reports and all available paraffin-embedded, hematoxylin-eosin-stained sections from all neoplasms were reviewed by three pathologists (SK, PD, JL). Special stains (alcian green, Verhoeff's elastica, reticulin, periodic acid-Schiff, and acid-fast for Mycobacterium tuberculosis) were available in f o u r cases. Although hematoxylin-eosin-stained sections of the primary tumor could not be reviewed in two patients (cases 9 and 10), the original report was available from case 9 and metastatic t u m o r tissue from the other. When available, nonneoplastic salivary gland tissue adjacent to the lesion was reviewed for evidence o f BLEL or other pathologic changes. Immunologic Studies
Serum antibodies to EBV were tested with indirect immunofluorescence36-2s Specifically, IgA and IgG titers to viral capsid antigen, the restricted and diffuse components o f the early antigen complex, and the viral nuclear antigen were determined in 13 patients. EBV DNA in the tumor tissue of two patients was tested by DNA hybridization methods. 29 HLA testing o f blood from six patients was done by the lymphocyte microcytotoxicity method, s~ Sera from 11 patients were tested by the Ouchterlony gel double-immunodiffusion technique and by the direct immunofluorescence method for antibodies characteristic o f a u t o i m m u n e disease. Sera were, tested at several dilutions for Sj6gren's syndrome antibodies A, B, and C (SS-A, -B, -(3) using a whole cell sonicate of Wil-2 cells. 31,32 The sera were also screened for Sm and U 1-ribonucleoprotein antibodies against h u m a n spleen and calf thymus extracts. Antinuclear antibody was studied by indirect immunofluorescence at a 1:30 serum dilution in an HEP-2 tissue culture substrate, s2 RESULTS Epidemiologic, Clinical, a n d M o r p h o l o g i c Studies
During the 15 years from 1966 to 1980, primary major salivary gland cancers were identified in 16 Alaskan Natives living in Alaska. Distribution o f these 16 patients by age and sex and the incidence rates are given in table 1. Five of 16 patients were men, and 11 were women. Average annual incident rates per 100,000 population, adjusted to the world
TABLE 1. Age and Sex Distribution of 16 Alaskan Natives with Primary Major Salivary Gland Cancers*
Age at diagnosis(yr) <30 30-39 40-49 50-59 ~>60 Total Crude ratet Age-adjusted rate~ Observed:expected ratio
Men
Women
1 0 1 2 1 5 1.17 1.73 1.7
1 5 2 3 0 I1 2.63 3.31 4.7w
* Excludes two native women,one diagnosed in 1960 and another diagnosed while residing outside Alaska. t Incidencerate per 105 population based on 1973 projections from the 1970 census data. :~Adjusted to the world standard population35 wP < 0.05. standard population, were 1.73 in men and 3.31 in women. Alaskan native women had nearly five times the risk o f developing salivary gland cancer as white women in the United States (observed:expected ratio, 4.7; P < 0.05). The observed:expected ratio in men was 1.7, wlfich is not statistically significant. Eleven o f the 16 patients were Eskimo and five were Indian. Twelve of the 16 primary salivary gland malignancies were diagnosed as MLEL, two as adenoid cystic carcinoma, one as an adenocarcinoma (unspecified), and one as a low-grade mucoepidermoid carcinoma. Two other patients with MLEL, one diagnosed prior to 1966 and anotber a nonresident of Alaska at the time of diagnosis, were excluded from rate calculations but included in the clinical and morphologic review (table 2). Nine of tile patients with MLEL were Eskimo and three were Athabaskan Indian. T h e Eskimo patients were almost equally divided a m o n g Yupik-speaking (five) and Inupiaqspeaking (four) Eskimo linguistic groups. Women p r e d o m i n a t e d a m o n g both Eskimo (male:female ratio, 3:6) and Athabaskan I n d i a n (male:female ratio, 0:3) groups. The median age at diagnosis of MLEL was 44 years in men and 36 years in women. T h e r e was no apparent regional clustering o f patients by birthplace or residence at diagnosis. None of the patients were first-degree relatives. T h e diagnosis of BLEL was made in three patients (one Aleut, two Tlingit Indian) during the period 1966-1980. Because surveillance and registration o f benign tumors was not as complete as those for malignant lesions, this may be an underestimate. T h e t h r e e patients with benign lesions are alive without recurrence of tumor seven to 13 years after superficial parotidectomy. Two have rheumatoid arthritis. All neoplasms involved the parotid gland except in three patients (table 2). Histologic features of the lymphoepithelial lesions suggested the n e o p l a s m s were in a continuum from benign lesions at one end to high-grade malignant tumors at the other, with low-grade MLEL in between (table 3). Eight patients had high-grade malignant tumors. T h e original neo987
HUMAN PATHOLOGY
Volume 18, No, 10 (October '1987}
TABLE 2.
Clinical and Morphologic Data on Alaskan
Year of Diagnosis
Age at Diagnosis(yr)
Sex
Ethnicity*
1969 1972 1975
46 33 42
F M M
Indian(Tl) Indian(Tl) Aleut
3 mo, slowly enlarging 3 wk, painless, enlarging 1 yr, slowly enlarging
1977 1971 1969 1969 1970
17 35 52 39 32
F F F F F
Eskimo(Y) Eskimo(Y) Eskimo(In) Eskimo(Y) Indian(Ath)
2 yr, painless 1 yr, painless, slowly enlarging 1 mo, tender, fixed Incidental finding 1 yr, varying size, slightly tender
1960
49
F
Eskimo(Y)
Gradually increasing, painless
1969
47
M
Eskimo(Y)
ll 12
1968 1969
30 26
F M
Indian(Ath) Eskimo(In)
Incidental finding, hard, slightly tender 6 too, tender, rock hard 2 mo, VII nerve involvement
13
1971
31
F
Eskimo(In)
14 15 16tt 17
1974 1976 1973 1980
44 44 29 58
F F F M
Eskimo(In) Indian(Ath) Eskimo(Y) Eskimo(Y)
4 yr, increasing; 6 mo, painless, fixed 5 mo, mass 1 yr, slowlyenlarging, painful Lump behind ear 6 too, slowlyenlarging, painful, hard
1968 1970 1972 1975
70 50 56 59
M F M F
Eskimo(In) Eskimo(In) Indian(Ath) Indian(Ath)
Enlarging mass Unknown Mass Massfor )-ears; recently enlarging, painful, tender
Case Benign iymphoepithelial lesions 1 2 3 Malignant lymphoepithelial lesions, low-grade 4 5 6 7 8 9tt Malignant lymphoepithelial lesions, high-grade 10
Other carcinomas 18 19 20 21
Duration and Clinical Characteristicst
* Subgroups are identified in parentheses: for Indians, Tlingit (TI) and Athabaskan (Ath); for Eskimos, Inupiat (In) and Yupik (Y). t All tumors involved tile parotid gland except in cases 1, 14, and 17. ~tLocal indicates tumor confined to gland; regional, gland and regional lymph nodes involved; distant, distant organ involvement. wTumor size based on clinical, not pathologic, examination is indicated in parentheses. 82H, hemimandibulectomy. ** To December 1982. [t Excluded from rate calculations. plasm was usually unifocal a n d infiltrated the surr o u n d i n g salivary gland (fig. 1A). Germinal centers were not observed in the l y m p h o i d c o m p o n e n t . Malignant cells were in disorderly sheets, trabeculae, or poorly d e f i n e d islands (fig. 1B). O v e r l a p p i n g o f cells f o r m e d syncytia with obscured cytoplasmic outlines (figs. 1B and C). Cellular p l e o m o r p h i s m o f polygonal o r spindle-shaped cells was observed (figs. 1B, 1C, a n d 1D). Nuclear chromatin was coarse o r c l u m p e d (Figs. 1C inset and 1D). F r e q u e n t mitoses a n d p r o m i n e n t , often nmltiple and p l e o m o r p h i c nucleoli were present. Anaplasia was r a r e a n d o n l y n o t e d in foci. Necrosis, s q u a m o u s metaplasia, and crush artifact were each observed in two patients. Fibroplasia was also observed. Carcinoma metastatic to l y m p h nodes had cellular detail similar to that o f the original t u m o r . Atypical and hyperplastic salivary ducts were n o t e d in the islands o f malignant cells. T h e ducts o f the s u r r o u n d i n g n o n n e o p l a s t i c salivary gland demonstrated atypical epithelial changes a n d l y m p h o i d cell infiltrates. T h e eight patients with high-grade M L E L died f r o m their neoplasm o r related complications eight 988
m o n t h s to five years a f t e r t r e a t m e n t (table 2). Prim a r y t h e r a p y included gland resection alone in o n e patient, g l a n d a n d radical neck dissection in five, gland resection a n d r a d i o t h e r a p y in one, and radiation alone in one. At diagnosis, extension o f disease into r e g i o n a l n o d e s was d o c u m e n t e d in six o f the eight patients; in two, staging was u n k n o w n . In o n e (case 10), the t u m o r was f o u n d incidentally o n physical e x a m i n a t i o n ; in cases 11 a n d 12, cervical l y m p h nodes were clinically negative, a l t h o u g h metastatic t u m o r was histologically d e m o n s t r a t e d in single l y m p h nodes in the dissected neck specimen. T h r e e patients h a d involvement o f only o n e l y m p h n o d e at initial histologic diagnosis. In these eight patients with h i g h - g r a d e MLEL, metastases subsequently developed in l y m p h nodes, liver, lungs, bones, and skin. T h e six patients whose tumors were classified as low-grade M L E L a p p e a r e d to have some m o r p h o logic features o f both benign and malignant lesions. T h e lesions were usually circumscribed but n o n e n capsulated, with areas o f infiltration into the surr o u n d i n g salivary gland. In contrast to the benign variant, the epithelial cell proliferation in low-grade M L E L was m o r e p r o n o u n c e d and d i s o r d e r l y , a n d
SALIVARYGLAND CANCERIN ALASKANNATIVES[Krishnamurthy et al,) Natives with Salivary Gland Neoplasms, 1966-1980 Initial Diagnosis and Treatment Extent ( n o d e s positive)*
T u m o r sizew (cm)
Follow-up**
Salivary Gland Surgery
Radical Neck Dissections~
Radiation
Recurrence
Metastases
Outcome (yr)
Tumor at Follow-up
Local Local Local
2 x 1.5 x 1 2 (clin) 3 x 2 (clin)
Excision Superficial Superficial
-
m
-
-
Alive (13) Alive (10) Alive (7)
-
Local Local Local Local Local
2.8 4 x 3 x 2 (clin) 1.6 2.5 1.8
+ +
m
-
-
Alive Alive Alive Alive Alive
(5) (11) (13) (13) (12)
-
Local
0.8
Superficial Superficial Superficial Superficial Superficial + deep Excision
-
+(x2)
-
Alive (22)
-
Unknown
1.8
Superficial
(Refused)
+
+
Dead (<1)
+
Regional Regional (1)
2 x 3 (clin) 1.8
+(H) +(H)
+
+ +
Dead (3) Dead (1)
+ +
Regional (26)
4 (clin)
Superficial Subtotal + total Total
+
+
Dead (2)
+
Regional (1) Regional Unknown Distant
2.2 4 (clin)
+ +
+ + + +
Dead Dead Dead Dead
(4) (5) (3) (<1)
+ + + +
Local Regional Local Regional
Unknown 2 Unknown
+ +
+ + +
Alive Dead Dead Dead
(7) (I) (7) (<1)
+ + +
7 x 6 x 4 (clin)
B
-
+
Total Total Total None
+ + ? -
+ + +
Total Total Total Total
+ (Refused) -
+ -
D
-
areas s h o w e d indistinct c y t o p l a s m s w h i c h i m p a r t e d a syncytial cellular a p p e a r a n c e . Cells w e r e usually in s h a r p l y d e f i n e d islands b u t s o m e t i m e s o c c u r r e d in sheets o r t r a b e c u l a e (figs. 2 A a n d 2B). T h e islands h a d v a r y i n g d e g r e e s o f p e r i p h e r a l p a l i s a d i n g (fig. ' 2C). N u c l e o l i w e r e p r o m i n e n t , usually single, eosinophilic, a n d u n i f o r m (fig. 2D). N u c l e a r c h r o m a t i n was v e s i c u l a r (fig. 2D). Mitoses w e r e r e a d i l y o b s e r v e d . Necrosis and anaplasia were not seen. The background lymphocytic infiltrate frequently included g e r m i n a l c e n t e r s . A b s e n c e o f l y m p h a t i c sinuses a n d fibrous trabeculae confirmed that these were not l y m p h n o d e s . D u c t o c e n t r i c l y m p h o i d cell a g g r e g a t e s a n d associated d u c t epithelial h y p e r p l a s i a a n d atypia w e r e m o r e p r o n o u n c e d in a d j a c e n t salivary g l a n d tissue t h a n in t h e g l a n d s o f patients with h i g h - g r a d e M L E L (fig. 3). T h e six p a t i e n t s with l o w - g r a d e M L E L a r e alive five to 22 y e a r s a f t e r diagnosis. N o n e o f t h e patients h a v e d e v e l o p e d metastases. T r e a t m e n t consisted o f g l a n d excision with o r w i t h o u t radical n e c k dissection (in two a n d f o u r patients, respectively). N o n e o f t h e patients r e c e i v e d i r r a d i a t i o n . A t diagnosis, t h e n e o p l a s m s h a d n o t e x t e n d e d b e y o n d t h e salivary g l a n d . Local r e c u r r e n c e a n d infiltration o f t u m o r d e v e l o p e d in case 9, b u t n o metastases h a v e d e v e l o p e d by 13 y e a r s a f t e r excision o f t h e s e c o n d r e c u r r e n c e . T h e o r i g i n a l a n d review m o r p h o l o g i c d i a g n o s e s w e r e c o m p a r e d . T h e r e was close a g r e e m e n t f o r B L E L a n d h i g h - g r a d e M L E L . H o w e v e r , as s h o w n in
-
-
table 4, t h e cases classified as l o w - g r a d e M L E L in this r e p o r t (cases 4 to 9) w e r e o r i g i n a l l y d i a g n o s e d as B L E L , B L E L with a t y p i a , l y m p h o e p i t h e l i a l lesion with focal anaplasia, p o o r l y d i f f e r e n t i a t e d c a r c i n o m a , and MLEL. P r e s e n t i n g s y m p t o m s a n d signs did n o t h e l p to d i f f e r e n t i a t e t h e t h r e e g r o u p s o f p a t i e n t s with lymp h o e p i t h e l i a l lesions. H o w e v e r , a h i s t o r y o f increase a n d d e c r e a s e in the size o f t h e lesion was d e s c r i b e d o n l y in p a t i e n t s with l o w - g r a d e M L E L . I n addition, a l t h o u g h h a r d n e s s o f t h e lesion was m e n t i o n e d in o n l y t h r e e o f t h e six patients with h i g h - g r a d e malign a n t lesions, it was n o t d e s c r i b e d in any, with b e n i g n o r l o w - g r a d e m a l i g n a n t t u m o r s (table 2). T w o o f t h r e e p a t i e n t s with B L E L (cases 2 a n d 3) h a v e develo p e d r h e u m a t o i d arthritis, w h e r e a s o n l y o n e o f the 14 p a t i e n t s with M L E L (case 7 with l o w - g r a d e M L E L ) has b e e n d i a g n o s e d with r h e u m a t o i d arthritis.
Immunologic Studies
Epstein-Barr Virus T e s t i n g f o r E B V a n t i b o d y was d o n e o n at least o n e s e r u m s a m p l e f r o m 13 d i f f e r e n t patients (table 5). S a m p l e s w e r e o b t a i n e d at d i a g n o s i s f r o m o n l y two patients (cases 4 a n d 17). E x c e p t f o r a n I g A a n t i viral c a p s i d a n t i g e n titer o f 1:10 in case 4 a n d a n I g G a n t i - e a r l y a n t i g e n (diffuse) titer o f 1:10 in case 17, the E B V titers w e r e n o t u n u s u a l f o r this p o p u l a t i o n a n d i n d i c a t e d past p r i m a r y E B V infection. 9
8
9
HUMAN PATHOLOGY
Volume 18, No. 10 (October 1987] TABLE 3.
Nonneoplastic Salivary Gland
Lymphoid Component
Neoplastic Component Islands, Sheets, Trabeculae
Lymphocytic Infiltrates
Germinal Centers
+++ + +
+++ +++ +++
++ +++
Islands Islands
Orderly Orderly
+ +
+
+
+
Islands
-
5
+
++
Islands
6
+
+
Islands
Orderly
+
7
+
+ Ductocentric + Ductocentric +
Orderly and disorderly Orderly
-
Disorderly
-
8
+
+
++
Islands, sheets, trabeculae Islands, sheets
Disorderly
•
+ +
+ +
+ -
Disorderly Disorderly
12 13
+ +
+ +
-
14 15 16
+ ++ +
+ ++ -
-
Islands, sheets Islands, sheets, trabeculae ND Sheets, trabeculae Islands, sheets Islands, sheets Sheets
Disorderly Disorderly Disorderly
17
ND
ND
ND
Sheets
Disorderly
Case Benign lymphoepithelial lesions 1" 2 3 Malignant lymphoepithelial lesions, low-grade 4
9t Malignant lymphoepithelial lesions, high-grade 10 11
Duct Hyperplasia
Histologic Features of SaIivary Grand
Orderly/ Disorderly
Disorderly Disorderly
Peripheral Palisading
++
F
ABBREVIATION:ND, not determined; material unsatisfactory or sampling insufficient. * Entire gland consisted of diffuse lymphocytic infiltrates with prominent areas of duct hyperptasia. No clearly identifiable neoplasm. "["Original material was not reviewed; it was reported as "benign lymphoepithelial lesion with foci of anaplasia." Single lymph node examined; no evidence of malignancy. S e r u m for EBV a n t i b o d y testing was o b t a i n e d at the t i m e o f r e c u r r e n t o r metastatic disease f r o m f o u r p a t i e n t s (cases 13, 14, 15, a n d 17). T w o p a t i e n t s (cases 14 a n d 17) s h o w e d an i n c r e a s e in n e a r l y all E B V antibodies with d e v e l o p m e n t o f distant metastases. H o w e v e r , o n e p a t i e n t (case 15) who d e v e l o p e d extensive metastatic disease a n d two (cases 13 a n d 14) with metastases involving only cervical l y m p h n o d e s did not show m a r k e d l y elevated EBV a n t i b o d y titers. T i t e r s w e r e w i t h i n n o r m a l limits in t h e r e m a i n i n g patients e x c e p t f o r two (cases 5 a n d 9). Six a n d f o u r s a m p l e s w e r e tested f r o m these two patients, respectively, a l t h o u g h results o f only the earliest a n d latest s e r u m s a m p l e s are listed in table 5. T h e s e two p a t i e n t s a r e alive a n d w i t h o u t t u m o r . S e r u m was o b t a i n e d f o r E B V testing at least f o u r years a f t e r s u r g e r y a n d s h o w e d persistently elevated I g A anti--viral capsid a n t i g e n a n d I g G a n t i - e a r l y antigen (restricted) titers, a n d in o n e patient a n t i - e a r l y a n t i g e n (diffuse) as well. Tests f o r EBV m a r k e r s in tissue were d o n e on two patients (cases 4 a n d 17). EBV D N A hybridization was positive in t u m o r tissue f r o m b o t h patients, while t o u c h p r e p a r a t i o n s f o r the viral n u c l e a r antigen w e r e positive only in case 17.
Human Leukocyte Antigen Results o f H L A typing studies a r e s h o w n in table 6. Six patients w e r e t y p e d mainly f o r loci A a n d B. N o p e r s o n s t y p e d w e r e B8. O n l y o n e p e r s o n was tested for D R antigens a n d he was f o u n d to be DRw4. T h i s patient h a d n o evidence o f r h e u m a t o i d arthritis o r related d i s o r d e r s .
Autoimmune Antibodies Results o f serologic tests for a u t o i m m u n e antibodies are s h o w n in table 7. Sj6gren's s y n d r o m e antibodies A a n d B (SS-A, -B) were not d e t e c t e d in a n y o f the 11 sera tested. SS-C or r h e u m a t o i d a n t i n u c l e a r antibody (reactive against extracts from EBV-infected B cells a n d t h o u g h t to be E p s t e i n - B a r r n u c l e a r antigen; C. Peebles, personal c o m m u n i c a t i o n , 1984) was identified in t h r e e patients, two o f w h o m h a d or d e v e l o p e d r h e u m a t o i d arthritis. Clinically significant titers o r a n t i n u c l e a r a n t i b o d y were not f o u n d by indir e c t i m m u n o f l u o r e s c e n c e in t h e I 0 p a t i e n t s with M L E L . T h e low titers o b s e r v e d in six o f these 10 patients were also f o u n d in sera tested at the s a m e time f r o m f o u r o f n i n e Alaskan Natives without salivary l y m p h o e p i t h e l i a l lesions. T h e only high titer was in 990
SALIVARYGLAND CANCER IN ALASKANNATIVES(Krishnamurthyet al.) Lymphoepithelial Lesions in Alaskan Natives Neoplastic Component
Sync)'tial/ Discrete
Pleomorphism
Nuclear Chromatin
! ncreased Nuclear-Q'toplasmic Ratio
Mitoses
Necrosis
m
m
-
ND Vesicular
. .
Syncytial and discrete Discrete
-
Vesicular
•
+
-
+
-
Vesicular
-
+
-
+
Syncytial and discrete
+
Vesicular
+
+
-
+ +
Syncytial and discrete Syncytial and discrete
•
Vesicular, coarse Vesicular, coarse
+
+
-
-
+
+
-
+
Syncytial Syncytial and discrete Syncytial Syncytial, crush Syncytial Syncytial Syncytial and discrete Syncytial
+ +
ND Coarse
+ +
+ +
+
+ +
+
+ +
Coarse Coarse
+ +
+ + + +
-
+ + (pleomorphic)
ND ND
+ + +-
Coarse Coarse Coarse, clumped Coarse
+ + •
+ + +
-
-
+
•
-
+ (pleomorphic) + (pleomorphic) + (pleomorphic, prominent) +
•
. .
Nucleolus
Discrete Discrete
•
. .
Anaplasia
Metastases or Infiltration
one patient with BLEL who also had rheumatoid arthritis. Antibody reactive to h u m a n spleen or calf thymus extracts was not detected in any of the 11 patients, except in one with a high-grade MLEL who had antibody to human spleen extract only. DISCUSSION
T h e data presented in this article support previous findings that Alaskan Natives, particularly w o m e n , are at increased risk for salivary gland cancer and that a large proportion (75 per cent) of the major salivary gland cancers are malignant lymphoepithelial lesions (MLEL). 2,s O f interest is that three patients with MLEL were Athabaskan Indian, not Eskimo. To date, there are no published reports of cases of MLEL in North American Indians outside Alaska, and data on salivary gland cancer among Indians in New Mexico and Arizona show no evidence of an excess risk. s2 Histologic, clinical, and follow-up findings from the patients reported in this article support the possibility of a spectrum of salivary lymphoepithelial lesions. In particular, a low-grade malignant lesion that does not metastasize but may recur locally appears to exist, a l t h o u g h it c a n n o t be d e t e r m i n e d clearly whether the favorable outcome of this group of patients was a result of early intervention or the in991
. .
+ + +
Unknown + + + + + - :[: +
herent nature of the lesion. Surgical treatment including gland resection and neck dissection without radiotherapy may suffice for this group of patients. On the other hand, gland resection and neck dissection, even in those who had only a single node involved at the time of diagnosis, did not prevent subsequent metastases and death. T h e major histoiogic features distinguishing low-grade MLEL include prominent but uniform nucleoli in the neoplastic cells; well-defined islands or sheets of cells; peripheral palisading; absence of necrosis and anaplasia; vesicular nuclear chromatin; and a lymphoid background that usually contains germinal centers. Duct epithelial hyperplasia, atypia, and lymphoid infiltrates, frequently ductocentric, are seen in the adjacent salivary gland. Metastases are not found. T h e background lymphoid infiltrate may also show a s p e c t r u m o f appearances, although in all three neoplastic groups that infiltrate was composed o f niature, well-differentiated, polymorphic lymphoid cells. In benign l y m p h o e p i t h e l i a l lesions (BLEL), the infiltrates were in multifocal aggregates that often showed germinal centers or in diffuse sheets extending throughout the salivary gland. The lymphoid infiltrates in low-grade MLEL were generally confined to the tumor. Germinal centers were present in some tumors. In high-grade MLEL, ger-
HUMAN PATHOLOGY
Volume l& No. 10 (October 1987)
FIGURE t. High-grade malignant lymphoepithelial lesion. A, Case 14. Neoplasm infiltrating salivary gland. B, Case 16. Syncytial arrangement of neoplastic cells obscuring cytoplasmic outlines. C, Case 12. Metastatic carcinoma In lymph node. Inset, Note coarse chromatin, syncyHal arrangement of neoplastic cells. D, Case 14. Spindle-shaped neoplastic cells with coarse chromatin. (Aft, hematoxylin-eosin stain. Original magnification: A, x 20; Band C, x50; insetand D, x125.]
992
SALIVARYGLAND CANCER IN ALASKANNATIVES(Krishnamurthy et al.)
FIGURE 2. Low-grade malignant lymphoepithelial lesion. A, Case 4. Sharply defined epithelial islands of neoplasiic cells in lymphocytic background. B, Case 5. Islands of neoplastic cells in lymphocytic background. C, Case 5. Peripheral paUsading. D, Case 8. Sharply defined cell islands, with prominent nucleoli and vesicular chromatin in neoplastic cells. (A//,hematoxylin-eosin stain. Original magnification: Aand D, x 125; B, x 100; C, x 200.)
993
HUMAN PATHOLOGY
Volume 18, No. 10 (October '1987)
FIGURE 3. Low-grade malignant
lymphoepithelial lesion. Case 8. Hyperplastic duct in nonneoplastic gland. (Hematoxylin-eosin stain. x `125.]
minal centers were not observed and the infiltrate was so dense as to suggest lymphoma. Although two patients in this series appeared to have had Epstein-Barr virus (EBV)-positive neoplasms as based on EBV DNA hybridization and viral nuclear antigen studies, serologic results at diagnosis were not typical of EBV-associated tumors. As has been described in patients with nasopharyngeal carcinoma, increases in EBV antibody titers were documented in two patients with MLEL who developed metastases. In two other patients, who did not develop recurrent tumors or metastases, persistently elevated EBV antibody titers were present. T h e reason for these antibody patterns are not clear at this time. Initial and Review Histologic Diagnoses in Cases of Low-grade Malignant Lymphoepithelial Lesions
TABLE 4.
Case 4 5 6 7 8 9
Initial Diagnosis*
ReviewDiagnosis
BLEL(2); LEL,NOS (1); BLELwith MLEL,low-grade atypia (1) BLEL(2); MLEL(1); anaplasticLEL MLEL,low-grade (2) BLEL(2); BLELwith mitosesand MLEL,low-grade atypia (1) BLEL(1); squamouscell carcinoma MLEL,low-grade with lymphoepithelialareas (1); MLEL(1) MLEL,low-grade Poorly differentiatedsquamouscelt carcinoma (1); MLEL(I) BLEL(1); LEL with focalanaplasia Original material (1); Mikulicz'sdisease (1); poorly not reviewed differentiatedcarcinoma(2)
ABBREVIATIONS:BLEL,benign lymphoepitheliallesion, LEL, lymphoepithelial lesion; MLEL, malignant Iymphoepitheliallesion; NOS, not otherwisespecified. * Numbers in parentheses indicatethe number of pathologists making the diagnosis. 994
Benign lymphoepithelial lesion may occur alone or in association with Sj6gren's syndromeJ ~-14 Although patients with Sj63gren's syndrome are at increased risk for cancer, 3 the malignancies that develop mainly arise in l y m p h o i d , not epithelial, cells, l~ MLEL is an undifferentiated or poorly differentiated carcinoma that is frequently fatalJ ,5-x~ These tumors have not been associated with SjOgren's syndrome or other autoimmune phenomena. In this series, two of the three patients with benign lesions had rheumatoid arthritis, and one with lowgrade malignant lesions developed rheumatoid arthritis five years after resection of her neoplasm. No other patient with MLEL had Sjrgren's syndrome, arthritis, or related disorders. In primary Sjrgren's syndrome, SS-A and -B an- 9 tibodies are found, whereas SS-C and anti-salivary gland antibodies are n o t J 3 In contrast, the absence of SS-A and -B antibodies but the presence of SS-C and anti-salivary gland antibody characterize secondary Sj6gren's s y n d r o m e with r h e u m a t o i d arthritis, ss BLEL is a feature of Sjrgren's syndrome. 12,1~,sl,s3 Serologic tests in 1 1 patients were negative for antibodies frequently found in Sj6gren's syndrome and other autoimmune diseases, despite the fact that histologic findings were similar to those found in BLEL and Sjrgren's syndrome. T h e term malignant lymphoepithelial lesion was used originally because some patients with neoplasms that had many features o f BLEL were observed to have a fatal outcome. 6 T h e difficulty in determining the original diagnosis in some patients in the current series (table 4) a n d the clinical and morphologic findings on review suggest that the benign and malignant lesions represent poles of a spectrum and may evolve from the same disease process. Unanswered questions remain. Should MLEL be
SALIVARYGLAND CANCERIN ALASKANNATIVES[Krishnamurthy et al.) TABLE 5.
Epstein-Barr Virus Antibody Titer in Alaska Natives with Lymphoepithelial Lesions of the Salivary Glands
Case Benign lymphoepithelial lesion 1 2 3 Malignant lymphoepithelial lesion, low-grade 4
Date of Diagnosis
Date of Sample
2/69 3/72 1/75
08/75 05/72 05/82
6/77
06/77 12183 08175 01/79 04172 09/79 03/72 03/79 08/75
5
3171
6
3/69
7
5/69
8
1/70
Clinical Findings
IgA VCA
IgG VCA
IgA EA-D
Localized Localized Localized
<10 <10 <10
80 80 640
<'1~) <10
Localized
10 <10 40 40 < 10 <10 <10 <10 <10
320 160 320 1280 160 160 160 80 80
Localized Localized Localized Localized
03/83
9
6/60
Malignant lymphoepithelial lesion, high-grade 13 14 15 17
7171 5/74 11/76 8/80
<10
80
08/75 08/83
(Recurrences in 1964, 1969)
<10 80
320 640
04/72 08177 10/78 03/82 08/80 01/81
Nodes Nodes Metastases Metastases
<10 <10 10 <10 <10 40
80 160 640 320 320 640
Metastases
IgG EA-D (R) <10
<10 <10 ~:'1() <'1~) <10 <10
<'1() ... ... <'1() <10 <10
EBNA
40 160 80
<10 <10 20 10 (80) < 10 <10 <10
320 160 80 80 80 80 40 160 20
.
<10
40
<10 <10 (80)
80 80
<10 <10 80 10 I0 40
160 40 80 40 40 40
ABBREVIATIONS:VCA, viral capsid antigen; EA, early antigen; D, diffuse component; R, restricted component; EBNA, Epstein-Barr nuclear antigen.
classified separately or simply g r o u p e d with other anaplastic carcinomas? Do some forms of MLEL have a biologically less malignant course? What is the relationship, if any, between BLEL and MLEL? Is there a common factor between MLEL and nasopharyngeal carcinoma in view of their histologic similarity and reported joint occurrence in both Eskimo and Chinese populations? What is the role of EBV in these lesions? Some o f these questions could b e a d d r e s s e d by the following studies: standardized review of all cases of MLEL reported to date; review of salivary gland cancers outside the circumpolar region and especially in areas at high risk for nasopharyngeal carcinoma; and detailed clinical, morphologic, viral, and a u t o i m m u n e antibody studies o f newly diagnosed cases. In summary, our study substantiates previous findings o f an increased risk in Alaskan Native
w o m e n f o r salivary gland cancer. Most o f these cancers were MLEL or undifferentiated carcinoma. A group o f patients were identified whose neoplasms were diagnosed as low-grade malignancy and did not metastasize, although one of these tumors recurred locally. Clinical and morphological features of this group were intermediate between BLEL and metastasizing, high-grade MLEL. Abnormal EBV titers were found in five of 12 patients, and EBV DNA was identified in the tumor tissue of two patients. SS-A and -B antibodies were not detected in any of 11 patients tested, including 10 with MLEL. T h e small number o f patients in whom these observations were made precludes firm conclusions: A study of all case material available internationally may help shed light on this unique neoplasm.
Acknowledgments. T h e authors t h a n k E. M. T a n , MD, PhD, a n d Carol Peebles, Scripps Clinic a n d Research Center, LaJolla, California, for testing for Sj6gren's synd r o m e a n d other a u t o i m m u n e antibodies.
TABLE 6.
Human Leukocyte Antigens in Alaskan Natives with Salivary Gland Lymphoepithelial Lesions
HLA Loci and Antigen Case
a
I
2,24
7,27
5 7
2,24 2
27 27,40
8 9 17
B
2,24 35,40 1 1 , 2 4 5,15 24,28 27,61
C
DR
2,4 4
Clinical Findings
Pathologic Diagnosis
REFERENCES 1. Nielsen NH, Mikkelsen F, Hansen JP: Incidence of salivary gland neoplasms in Greenland with special reference to an anaplastic carcinoma. Acta Pathol Microbiol 8cand [A] 86:185, 1978 2. Lanier AP, Bender TR, Blot WJ, et al: Cancer incidence in Alaska natives. IntJ Cancer 18:409, 1976 3. Lanier AP, Bender TR, Blot WJ, et al: Cancer in Alaskan natives: 1974-78. Natl Cancer Inst Monogr 62:79, 1982 4. Wallace AC, MacDougall JT, Hildes JA, et al: Salivary gland tumors in Canadian Eskimos. Cancer 16:1338, 1963 5. Arthaud JB. Anaplastic parotid carcinoma ("malignant lym-
Rheumatoid BLEL arthritis MLEL, low-grade Rheumatoid MLEL, low-grade arthritis MLEL, low-grade MLEL, low-grade MLEL, high-grade
ABBREVIATIONS: BLEL, benign lymphoepithelial lesion; MLEL, malignant lymphoepithelial lesion.
995
HUMAN PATHOLOGY
Volume 18, No. 10 (October 1987]
TABLE 7, Serum Autoantibodies in Alaskan Natives with Salivary Gland Lymphoeplthelial Lesions SS-Antibodies*t Case Benign lymphoepithelial lesion 382 Malignant lymphoepithelial lesion, low-grade 4 5 6 7 82
8 9 Malignant iymphoepithelial lesion, high-grade 13 14 15 17
Date of Diagnosis
Date of Sample
A
B
c
FANA$
HSE/CTEw
1/75
5/82
-
-
+ (>4)
3+
-
6/77 3171 3/69 5/69 1170 6/60
6/77 8/75 10178 3/72 8/75 8/75
. . -
.
1+
_/-
7/71 5174 11176 8/80
4/72 8/77 12181 8/80
. -
.
. -
.
.
. -
. . -
I +
-
-
-
1+
-
1+ 1+
+/---/-
1+
-
.
+ (4) .
-
.
+ (4)
.
* Titers are reciprocal of highest dilution. t Sj6gren's syndrome (SS) antibodies A, B, and G (or rheumatoid antinuclear antibody, RANA). Antigen source was Wil-2 cell sonicate. Titers ~ 1:4 dilution are considered positive. ~: Indirect fluorescent antinuclear antibody (FANA) using tissue culture human epithelial cell line (HEp-2) substrate and serum at 1 : 3 0 dilution. 1-1 + = low positive; 2 + = moderate positive; ~>3-4 + = strong positive w HSE, human spleen extract; CTE, calf thymus extract. 82Case 3 had rheumatoid arthritis at time of diagnosis of tumor; Case 7 was diagnosed with rheumatoid arthritis in 1974.
6. 7. 8. 9. 10.
11. 12. 13. 14. 15. 16. 17. 18.
19. 20.
phoepithelial lesion") in seven Alaskan natives. Am J Clin Pathol 57:275, 1972 Hilderman WC, Gordon JS, Large HL, et al: Malignant lymphoepithelial lesion with carcinomatous component apparendy arising in parotid gland. Cancer 15:606, 1962 Gravanis MB, Giansanti JS: Malignant histopathologic counterpart o f the benign lymphoepithelial lesion. Cancer 26:1332, 1970 Ferlito A, Donati LF: Malignant lymphoepithelial lesions. J Laryngol Otol 91:869, 1977 Nagao K, Matsuzaki O, Saiga H, et al: A histopathologic study of benign and malignant lymphoepithelial lesions of the parotid gland. Cancer 52:1044, 1983 Thackray AC, Lucas RB: Tumors of the major salivary glands. In Firmingen HI (ed): Atlas of T u m o r Pathology, 2nd series, fascicle 10. Washington, DC, Armed Forces Institute of Pathology, 1974 Dong H, Lo G: Malignant lymphoepithelial lesions of the salivary glands with anaplastic carcinomatous changes. Cancer 52:2245, 1983 Godwin J T : Benign lymphoepithelial lesion of the parotid gland. Cancer 5:1089, 1952 Morgan WS, Castleman B: A clinicopathologic study of "Mikulicz's disease." A m J Pathol 29:471, 1953 Evans RW, Cruikshank AH: Epithelial Tumors of the Salivary Glands. Philadelphia, WB Saunders, 1970 Thackray AC, Sobin LH: Histological typing of salivary gland tumors. In International Histological Classification o f Tumors, no. 7. Geneva, World Health Organization, 1972 Batsakis JG, Gernacki EG, Rice DH, et ah Malignancy and benign lymphoepithelial lesion. Laryngoscope 15:389, 1975 Pinkus GS, Dekker A: Benign lymphoepithelial lesion of the parotid glands associated with reticulin cell sarcoma. Cancer 25:121, 1970 Shanmugarathnam K: Histological typing of nasopharyngeal carcinoma. In De-the GG, Ito Y (eds): Nasopharyngeal Carcinoma: Etiology and Control. IARC scientific publications no. 20. Lyon, International Agency for Research on Cancer, 1978 Henle W, Henle G. Epidemiologic aspects of Epstein-Barr virus (EBV)-associated diseases. Ann NY Acad Sci 354:326, 1980 Lanier AP, Bornkamm GW, Henle W, et al: Association of Epstein-Barr virus with nasopharyngeal carcinoma in
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26. 27. 28. 29.
30. 31. 32.
33.
996
Alaskan native patients: serum antibodies and tissue EBNA and DNA. I n t J Cancer 28:301, 1981 Saemundsen AK, Albeck H, Hansen JPH, et al: Epstein-Barr virus in nasopharyngeal and salivary gland carcinomas of Greenland Eskimos. B r J Cancer 46:721, 1982 1970 Census of Population, vol I, pt 3. Washington, DC, Bureau o f the Census, US Department of Commerce, I973, pp 205 Cutler SJ, Young J L J r (eds): Third National Cancer Survey: Incidence Data. Washington, DC, National Cancer Institute, 1975 Bailar JC III, Ederer F: Significance factors for the ratio of a Poisson variable to its expectations. Biometrics 202:639, 1964 Waterhouse J, Muir C, Correa P, et al (eds): Cancer Incidence in Five Continents, vol III. IARC Scientific Publications no. 15. Lyon, International Agency for Research on Cancer, 1976 Henle G, Henle W: Epstein-Barr-virus-specific IgA serum antibodies as an outstanding feature of nasopharyngeal carcinoma. I n t J Cancer 17:1, 1976 Henle G, Henle W, Horowitz CA: Antibodies to Epstein-Barrvirus-associated nuclear antigen in infectious mononucleosis. J Infect Dis 130:231, 1974 Henle W, Henle G, Horowitz CA: Epstein-Barr virus-specific diagnostic tests in infectious mononucleosis. HUM PATHOL 5:551, 1974 Bornkamm GW, Stein H, Lennert K, et al: Attempts tO demonstrate virus-specific sequences in human tumors: IV. EB viral DNA in European Burkitt lymphoma and immunoblastic lymphadenopathy with excessive plasmacytosis. I n t J Cancer 17:177, 1976 Terasaki PI, Bernoco D, Parks MS, et al: Microdroplet testing for HLA-A, -B, -C, and -D antigens. Am J Clin Pathol 69:103, 1978 Alspaugh M, Tan EM: Antibodies to cellular antigens in Sjogren's syndrome. J Clin Invest 55:1067, 1975 Y o u n g J L J r , Percy CL, Asire AJ (eds): Surveillance, epidemiology, and end results: incidence and mortality data, 1973-1977. N I H publication no. 81-2330. Natl Cancer Inst Monogr 57:122, 1981 Moutsopoulos HM, Chased TM, Mann DL, et al: Sjogren's syndrome (sicca syndrome): current issues. Ann Intern Med 92(2 pt 1):212, 1980