Peripheral (extraosseous) calcifying odontogenic cyst

Peripheral (extraosseous) calcifying odontogenic cyst A review of forty-five

cases

Amos Buchner, DiUD, A4SD,aPhillip W. Merrell, DDS,b Louis S. Hansen, DDS, MS, MBA,c and Alan S. Leider, DDS, i14A,d San Francisco, Calif UNIVERSITY

OF THE

FRANCISCO,

SCHOOL

PACIFIC

SCHOOL

OF DENTISTRY

AND

UNIVERSITY

OF CALIFORNIA,

SAN

OF DENTISTRY

The peripheral calcifying odontogenic cyst (PCOC) is a rare lesion. The number of well-documented cases reported in the English-language literature until now is 38. The purpose of the present study is twofold: (1) to report seven new cases of PCOC and (2) to review and analyze the clinical and histomorphologic features of the previously reported cases of PCOC together with those of the present study. Most of the lesions were located in the maxillary and mandibular gingiva or alveolar mucosa anterior to the region of the first molar. Histologically, 66% of the lesions were of the cystic variant and 34% of the solid (neoplastic) variant. The terminology of the lesion and its histogenesis are discussed.

(ORALSURCORALMEDORAL PATHOL1991;72:65-70)

T

he calcifying odontogenic cyst (COC) was first recognized as a distinct entity by Gorlin et al.’ in 1962. It is generally regarded as a benign lesion of odontogenic origin, which can present as either a cyst or a neoplasm. In 1981 Praetorius et a1.2classified the COC into two main types: cystic and neoplastic (solid). They proposed the term “dentinogenic ghost cell tumor” for the neoplastic type. Most casesof COC arise centrally within bone, but occasionally they may occur peripherally. The peripheral calcifying odontogenic cyst (PCOC), also known as the extraosseousCOC or the COC of soft tissues, is a lesion with the histologic characteristics of an intraosseous COC but occurs in the soft tissues overlying the tooth-bearing areas of the maxilla and mandible. PCOC is a rare lesion. The total number of cases Wisiting Professor, Division of Oral Pathology, University of the Pacific. bAssociate Professor, Division of Oral Pathology, University of the Pacific. CProfessor, Division of Oral Pathology, University of California, San Francisco. dProfessor and Head, Division of Oral Pathology, University of the Pacific.

7/14/30286

reported in the English-language literature until now is 38, and most of them appear as isolated casereports or reports of a small series of cases. The purpose of the. present study is twofold: (1) to add sevennew casesof PCOC to the literature and (2) to review the previously reported cases of PCOC, which, together with those of the present study, give a total of 45 acceptable casesfor evaluation and analysis. MATERIAL

AND METHODS

The files of the Division of Oral Pathology, University of the Pacific School of Dentistry, and the Division of Oral Pathology, University of California, San Francisco, served as a source of material for this study. Seven specimensdiagnosed as PCOC were retrieved from the files and evaluated. Clinical information for the study was obtained from the submitted biopsy request forms. To record the location of the lesions, the gingiva was divided into three anatomic regions: incisor-cuspid, premolar, and molar-retromolar. Lesions involving more than one region were assigned to the one in which the greatest portion of the lesion was present. The race of the patients was classified into four groups: white, black, Asian, and Hispanic. 65

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Buchner et al.

ORAL SURGORAL MED ORAL PATHOL July 1991

Table I. Clinical data of seven casesof PCOC Case No.

Age (vr)/ gender

Race

Gingival location

Mandible, lateral incisor, cuspid Mandible, edentulous lateral incisor, cuspid Mandible, central incisor Mandible, retromolar Mandible, edentulous ridge Mandible, edentulous cuspid, first premolar Mandible, edentulous cuspid, first premolar

I

56/M

Black

2

72/M

White

3 4 5 6

IO/M 77/F 53/F 92/F

Black White White White

7

70/F

White

Size fcm)

Duration

0.7

6 mo

Fibroma/PGCG

0.5

1 mo

Gingival cyst

0.5 0.8 1.1 1.0

6 mo Unknown Unknown 6 mo

Fibroma Mucocele/SGT Fibroma Fibroma/PGCG

0.5

10

Clinical diagnosis

yr

Gingival cyst/ PGCG

PGCG, Peripheral giant cell granuloma; SGT, salivary gland tumor.

Table II. Histologic features of seven casesof

PCOC

Age

Case No. Architecture 1 2 3 4 5

6 7 *Minimal

Table Ill. Gender and age distribution by decade

Cystic Cystic Solid Cystic Solid Solid Cystic

Ghost cell mineralization

No Minimal* Minimal Minimal Yes Yes Yes

refers to mineralization

Dentinoid

Yes Yes Yes Yes Yes Yes Yes

Foreign body reaction

Yes No No No Yes No Yes

only in isolated cells.

Review of theliterature included only articles published in English. The search disclosed 38 casesthat were reported as PCOC occurring in the gingiva and alveolar mucosa.tS2’A case of PCOC located in the parotid salivary gland3 and a case that presented clinically as an eruption cyst associatedwith a deciduous tooth2 were excluded from the study. A case of “peripheral odontogenic tumor with ghost-cell keratinization”22 was also excluded becauseseveral consultants did not interpret it as PCOC. RESULTS

The clinical data of the seven casesof PCOC are shown in Table I. All the lesions were located in the mandible and presented as smooth-surfaced, pink to reddish, exophytic masses.Four lesions exhibited a firm consistency, and three were described as cystic lesions (cases2,4, and 7). In one case (case 3) pressure resorption of the underlying bone and displacement of adjacent teeth were noticed. The lesions were treated by simple excision, and no recurrences were recorded. The histopathologic features of the seven lesions are depicted in Table II. Four lesions exhibited a cystic architecture and three were mainly solid (Figs. 1

grw W o-9 10-19 20-29 30-39 40-49 50-59 60-69 IO-19 80-89 90-99

Total

No. of cases % of

F

Total

cases

0

1

I

0

1 2 2 6 2 6 3

8 2 4 4 II 4 I 3

21

I -ii

1 45

2.2 17.8 4.4 8.9 8.9 24.4 8.9 15.6 6.7 2.2

M 1 I I 2 2 5 2

1 2

100.0

to 4). Islands and strands of odontogenic epithelium were present in the wall of the cystic lesions, but in one case (case 1) they were extensive. In two lesions (cases 5 and 7) there was continuity between the lesion and the surface epithelium. In one lesion (case 5), in addition to dentinoid, areas resembling tubular dentin and dental papilla were also noticed. However, no enamel or enamel matrix could be identified. The following data are based on the combined analysis of 38 casesfrom the literature and sevencases of the present study. Age, gender distribution,

and race

The patient’s age at the time of excision was known in all casesand ranged from 9 to 92 years, with a mean of 48.4 years (Table III). The highest incidence was in the sixth to eighth decadesof life, with 49% of the patients in these age groups. However, there was also a peak in the second decade (18%). Of the 45 cases, 24 (53%) were in females and 21 (47%) were in males. The race of the patients was reported for only 22 cases.Fourteen cases(64%) were in whites, six (27%)

Peripheral calcifying odontogenic cyst 67

Volume72 Number 1

Fig. 1. Low magnification of PCOC (cystic type) lying entirely within gingiva. Note focal thickening of epithelial lining (G). On high magnification this area was found to be composedof ghost cells. Dark areas in lumen of cyst represent surgical hemorrhage. (Original magnification, x5.)

Fig. 3. Sheets of fused ghost cells (G) and dentinoid (0) in wall of cyst. (Original magnification, X50.)

Fig. 4. Portion of PCOC (solid type). Note in fibrous connective tissue a large epithelial island with peripheral palisading, stellate reticulum-like cells, ghost cells, and calcification. Dentinoid is present in connective tissue in close association with odontogenic epithelium. (Original magnification, X25.)

Fig. 2. Abundant keratinized ghost cells in epithelial lining of cyst. (Original magnification, X50.)

were in blacks, and one case each was found in an Hispanic and an Asian. The predominance in a specific race, however, is difficult to evaluate from a review of the English-language literature only. Location

Table IV shows the location of the lesions on the gingiva and alveolar mucosa. The mandible was the

more common site for PCOC, as shown by the occurrence of 26 (58%) of the lesions in the mandible and 19 (42%) of the lesions in the maxilla. The two most common locations were the incisor-cuspid region and the premolar region. Only a few lesions were located in the molar-retromolar region. Clinical

features

Almost all the lesions appeared as circumscribed, smooth-surfaced elevated masseson the gingiva or alveolar mucosa. One lesion exhibited a papillary surface. Most were described by the clinicians as firm swellings, and a few as soft swellings or cysts. The color was usually normal except for somelesions that

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Buchner et al.

Table IV.

ORAL SURG ORAL MED ORAL PATHOL July 1991

Location of lesions on gingiva No. of cases

Location Mandible Incisor-cuspid region Premolar region Molar-retromolar region Unknown Maxilla Incisor-cuspid region Premolar region Molar-retromolar region Unknown *Location

Labial/buccal gingiva

3 3

0 3*

Edentulous ridge

Total No.

2 2

3 3

I3

0 0

1 I

4

6

2 0 0 0

11 3 I 4

0 I I

8 I

was designated as “posterior to canine.“*’

were reddish. The size of the lesion was known in 21 casesand ranged from 0.5 to 4.0 cm. Most of the lesions (80%) were in the range of 0.5 to 1.1 cm in their greatest diameter, and only four were larger (1.5,2.0, 3.0, and 4.0 cm). The mean size was 1.l cm. Almost all the lesions were asymptomatic and were detected during routine oral examination. Only four patients had a recent progressive enlargement. The duration of the lesion was reported in 14 cases and ranged from 1 month to 15 years. In sevencasesthe duration ranged from 1 to 8 months and in the remaining sevenit was reported in terms of 2,3,5,7, and 10 years, with two patients having a history of 15 years. In 11 cases a superficial saucerization of the underlying bone was noted at surgery. In two additional cases the saucerization was marked and was manifested in preoperative radiographs as a radiolucent lesion.3,6 In three casesdisplacement of adjacent teeth was reported. A variety of clinical diagnoses were made by the clinicians; the most common were fibroma or fibrous hyperplasia. Other diagnoses were in the category of cystic lesions (gingival cyst, odontogenic cyst, nasolabial cyst, and mucocele). In a few casesthe diagnosis of peripheral giant cell granuloma or salivary gland tumor was considered. Histologic

Lingual/palatal gingiva

features

The PCOC exhibited the same histomorphologic features as seenin the intraosseous COC, including a cystic and a solid (neoplastic) variant. Information regarding the cystic or solid nature of the lesion was available for 38 cases.In 25 cases(64%) the lesions were cystic, and in 12 cases (36%) they were solid.

The cystic lesions usually exhibited a stratified epithelial lining with a distinct basal layer. The spinous layer resembled in certain areas the stellate reticulum of the enamel organ. The prominent feature of the lining was the presence of isolated “ghost” cells or groups of such cells. The “ghost” cells were sometimes mineralized. Dentinoid was usually noticed in the connective tissue and when present, it was in contact with the epithelium. In one case(case 2) tubular dentin and pulp tissue were present in the cyst wall but enamel was absent. All the lesions exhibited ghost cells. Most showed mineralization of ghost cells and dentinoid. However, somefeatured only ghost cells. Islands and strands of odontogenic epithelium were usually present in the connective tissue of the cyst wall, and in a few cases they were extensive. Foreign body reaction was also reported in several cases.This reaction was evoked by contact of the keratinized ghost cells with the connective tissue of the cyst. The solid (neoplastic) lesions were composed of numerous islands of odontogenic epithelium, varying in size, in a fibrous connective tissue stroma. Many of the large islands exhibited peripheral palisading, stellate reticulum-like arrangement, and ghost cells. Cysts or slits developed within someof the individual islands. Mineralization of ghost cells and formation of dentinoid in intimate contact with the epithelium were also common findings. In one case (present study) areas similar to tubular dentin and dental papilla were recognized. A foreign body reaction was observed in several cases. In four cases a continuity between the PCOC and the surface epithelium was recorded. A single caseof melanotic variant of PCOC has also been reported.17

Peripheral calcifying odontogenic cyst 69

Volume 72 Number 1

Treatment

and follow-up

The treatment of PCOC was usually simple excision, and, except for one case,no recurrences were recorded. The lesion recurred 3 years after the first surgery.r6 DISCUSSION

It is impossible to compare the clinical and histologic features of PCOC of the present study with the central lesions because all the reviews concerning COC until now combined the peripheral and the central lesions and treated them as a single entity.8, lo, 23 However, it was interesting to note that the mean age of the patients (48.4 years) is similar to that of patients with gingival cyst of the adult (mean age 48.2 years) and peripheral ameloblastoma (mean age 52.3 years).24,2s Our review of the literature revealed that PCOC are extremely rare lesions. However, there is a possibility that PCOC is somewhat more common but is not yet recognized as a specific entity by some oral pathologists. Nagao et al., 26who reviewed 23 casesof COC in the Japanese literature, did not find even a single case of PCOC. Although these authors could not give a definite reason for this phenomenon, they raised the possibility that casesof PCOC were classified in Japan into other categories such as peripheral ameloblastoma. Regarding the histogenesis of PCOC, two major sources of origin must be considered. Those lesions which are located entirely within the connective tissue of the gingiva and are separated from the surface epithelium by a band of connective tissue probably arise from remnants of the dental lamina (rests of Serres), whereasother lesions appear to arise from the surface epithelium. A similar histogenesishas been suggested for peripheral ameloblastoma and gingival cyst of the adult.23,24 The proper classification of the COC as a cyst or neoplasm has been debated since its establishment as an entity by Gorlin et al.’ Praetorius et al2 tried to resolve the situation when they concluded that the group of lesions diagnosed as COC subsumedtwo entities: a cyst and a neoplasm. They proposed the term “dentinogenic ghost cell tumor” for the neoplastic entity. Shear27 suggested that the term “dentinoameloblastoma” might be more appropriate for the neoplastic variant of COC, because it appears to be a variety of ameloblastoma. Recently Ellis and Shmookler28claimed that becausethe ghost cells are the most distinctive histologic feature, the term “epithelial odontogenic ghost cell tumor” should be preferred.

Praetorius et a1.2 suggested that the neoplastic variant of COC occurs in older patients. In the present study of PCOC, differences between the age distribution of the cystic and solid (neoplastic) lesions were not significant. There were no significant differences in the location of the cystic and solid (neoplastic) lesions in the mandible and maxilla. More data are neededon the cystic and solid (neoplastic) variants of PCOC to draw conclusions relative to any differences in their nature and biologic behavior. REFERENCES 1. Gorlin RJ, Pindborg JJ, Clausen FP, Vickers RA. The calci-

fying odontogenic cyst: a possible analogue of the cutaneous calcifying epithelioma of Malherbe. ORAL SURG ORAL MED ORAL PATHOL 1962;15:1235-43.

2. Praetorius F, Hjorting-Hansen E, Gorlin RJ, Vickers RA. Calcifying odontogenic cyst: range, variations and neoplastic . potential.-Acta Odontol Stand 1981;39:227-40. 3. Gorlin RJ. Pindbora JJ. Redman RS. Williamson JJ. Hansen LS. The calcifying idontogenic cyst: a new entity and possible analogue of the cutaneouscalcifying epithelioma of Malherbe. Cancer 1964;17:723-9. 4. Bhaskar SN. Gingival cyst and the keratinizing ameloblastoma. ORAL SURG ORAL MED ORAL PATHOL 1965;19:796-807. 5. Jones JH, McGowan DA, Gorman JM. Calcifying epithelial odontogenic and keratinizing odontogenic tumors. ORAL SURG ORAL MED ORAL PATHOL 1968;25:465-9.

Abrams AM, Howell FV. The calcifying odontogenic cyst. ORAL SURG ORAL MED ORAL PATHOL 1968;25:594-606.

Sauk JJ. Calcifying and keratinizing odontogenic cyst. J Oral Surg 1972;30:893-7. Fejerskov 0, Krogh J. The calcifying ghost cell odontogenic tumor--or the calcifying odontogenic cyst. J Oral Pathol 1972;1:273-87. 9. Anneroth G, Nordenram A. Calcifying odontogenic cyst. ORAL SURG ORAL MED ORAL PATHOL 1975;39:794-801.

IO. Freedman PD, Lumerman H, Gee JK. Calcifying odontogenic cyst: a review and analysis of seventy cases.ORAL SURC ORAL MED ORAL PATHOL 1975;40:93-106.

11. Chen SY, Miller AS. Ultrastructure of the keratinizing and calcifying odontogenic cyst. ORAL SURG ORAL MED ORAL PATHOL 1975;39:769-80.

12. McGowan RH, Browne RM. The calcifying odontogenic cyst: a problem of preoperative diagnosis. Br J Oral Surg 1982; 20:203-12. 13. Sawyer DR. Mosadomi A. Calcifying odontogenic cyst: report of four cases from Nigeria, West Africa. Cent Afr J Med 1983;29:196-9. 14. Dominguez FV, Espinal EG. The calcifying odontogenic cyst: clinical and histological analvsis of 10 cases. Acta Odontol Latinoam 1984;1:7?-83. I 15. Swan RH, Houston GD, Moore SP. Peripheral calcifying odontogenic cyst (Gorlin cyst). J Periodontol 1985;56:340-3. 16. Zachariades N. Unusual Gorlin cyst with traumatic neuroma. J Oral Med 1985;40:87-90. 17. Hirshberg A, Dayan D, Horowitz I. Dentinogenic ghost cell tumor. Int J Oral Maxillofac Surg 1987;16:620-5. 18. Siar CH, Ng KH, Sasidhar N. Melanotic extraosseouscalcifying odontogenic cyst. J Oral Med 1987;43:18l-3. 19. McClatchey KD, Stewart JCB, Patterson BD. Dentinogenic ghost cell tumor presenting as gingival mass. Ann Dent 1988;47:3l-2. 20. Keszler A, Bruzzone R, Sforza R. Peripheral calcifying odontogenic cyst. Ann Dent 1988;47:28-30.

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21. Shamaskin RG, Svirsky JA, Kaugars GE. Intraosseous and extraosseous calcifying odontogenic cyst (Gorlin cyst). J Oral Maxillofac Surg 1989;47:562-5. 22. Vuletin JC, Solomon MP, Pertschuk LP. Peripheral odontogenie tumor with ghost cell keratinization. ORAL SURC ORAL MED ORAL PATHOL 1978;45:406-I 5. 23. Altini M, Farman AC. The calcifying odontogenic cyst. ORAL SURG ORAL MED ORAL PATHOL 1975;40:751-9. 24. Buchner A, Sciubba JJ. Peripheral epithelial odontogenic tumors: a review. ORAL SURG ORAL MED ORAL PATHOL 1987; 63:688-97. 25. Buchner A, Hansen LS. The histomorphologic spectrum of the gingival cyst in the adult. ORAL SURG ORAL MED ORAL PATHOL 1979;48:532-9. 26. Nagao T, Nakajima T, Fukushima M, lshiki T. Calcifying

ORAL SURG ORAL MED ORAL PATHOL JULY 1991 odontogenic cyst: a survey of 23 cases in Japanese literature. J Maxillofac Surg 1983;11:174-9. 27. Shear M. Cysts of the jaws: recent advances. J Oral Pathol 1985;14:43-59. 28. Ellis CL, Shmookler BM. Aggressive (malignant?) epithelial odontogenic ghost cell tumor. ORAL SURC ORAL Mm ORAL PATHOL 1986;61:471-8. Reprint requests: Alan S. Leider, DDS, MA Division of Oral Pathology University of the Pacific School of Dentistry 2155 Webster St. San Francisco, CA 941 I5