Ossifying fibromyxoid tumor of soft parts in a child: A case report

Ossifying

Fibromyxoid

Tumor

By Rieko Ijiri, Yukichi

Tanaka,

of Soft Parts in a Child: Kazuaki Yokohama,

Ossifying fibromyxoid tumor (OFMT) is a relatively rare tumor, most of which occur in adults with preferential localization in subcutis or muscles of the extremeties. Although Schwannian or cartilage origin has been suggested, histogenesis of this tumor still is unclear. The authors present a 6-year-old girl with retroperitoneal OFMTshowing paraspinal extension, who is alive and tumor free 9 years after excision. The current case is the youngest reported patient showing

SSIFYING FIBROMYXOID TUMOR (OFMT), first described by Enzinger et al in 1989,’ is relatively rare with approximately 100 reported cases in the world literature. The tumor predominantly arises in adults with preferential localization in subcutaneous tissue or muscle of the upper and lower extremities. Only 4 patients under the age of 20 have been reported1 and the youngest was a 13-year-old boy.” The histogenesis of the tumor is still unclear, although Schwannian and chondroid origins have been discussed most frequently. We report a nonossifying variant of OFMT arising in a 6-year-old girl. The tumor, associated with a surgically identified spinal nerve, was located in the retroperitoneum with paraspinal (dumbbell) extension, strongly supporting Schwann as its origin.

Misugi,

Kenichi

Sekido,

A Case Report

and Toshiji

Nishi

Japan

unusual deep trunk site with surgically identified association with the spinal nerve. Both the clinical and histopathologic features strongly suggested Schwannian origin of this tumor. J Pediatr Surg 34:1294-1296. Copyright o 7999 by W.B. Saunders Company. INDEX neum,

WORDS: paraspinal,

Ossifying pathology.

fibromyxoid

tumor,

retroperito-

0

CASE

From the Department of Pathology, Kalzagawa Children’s Medxal Centel; Yokohama, Japan. Address reprint requests to Rleko Ijiri, MD, Kanagawa Children> Medical Centel; Department of Pathology, Minamiku Mutsukawa 2-138-4, Yokohama city, Kanagawa Prefecture 232, Japan. Copyright 0 1999 by WB. Saunders Company

1294

Preoperative

computed

tumor (single is noted.

tomographic

arrowhead)

with

scan. Left-sided retroparaspinal extension (double

REPORT

A 6-year-old girl was refered to our institution complaining of intermittent claudication and left foot pain. Results of routme laboratory studies were normal except for mild anemia. Urinary van~llylmandelic acid (VMA) and homovanillic acid (HVA) levels were within normal limits. Family and past histories were unremarkable. Computed tomographic scan (CT) showed a left-sided retroperitoneal tumor with paraspinal extension, compressmg the spinal cord toward the right side (Fig 1). Resection of the tumor was performed; first the intraspinal section and approxrmately 2 weeks later, the retroperitoneal tumor was resected. At the time of operation, a spinal tumor extended from L2 to L.5 wrth partial intradural invasion at L2 lesion. Attachments between the tumor and the spinal nerve roots (L4 and L5) were found. The retroperitoneal tumor measured 25 X 18 X 16 cm and was located at the vertebral foramen of L4. Both tumors were yellow-white and firm wrth encapsulation. No cysttc change, hemorrhage, or necrosis was noted.

0022-3468/99/3408-0026$03.00/O

Fig 1. peritoneal arrowhead)

Total resection of the tumor was possrble so that no adjuvant chemotherapy or radiation therapy was added. The patient is alive and tumor free 9 years later. Microscopically, the mass. which was surrounded by relatively thick nerve fibers, contamed sheet or cordlike proliferation of round to oval

Fig 2. of tumor

Journal

Characteristic cells.

offediatric

area showing

Surgery,

anastomosing

Vol 34, No 8 (August),

cords

and rows

1999, pp 1294-1296

OSSIFYING

FIBROMYXOID

TUMOR

1295

Table

1. Accumulative

of Clinical

14-79

et al’

(47)

Manifestation Naof

Age. yr (mean)

Study Enzinger

Results

LocatIon

CEiSeS

40

Upper/lower extremity

(59 cases)

11

Trunk Chest

wall

(9) (1)

Abdomen

Guarner et aI’3 Miettrner+ (4 cases)

51 39-86 (61)

Flank Head and neck

(1) 8

Upper extremity Upper/lower

1 2

Chest

Fig 3. fibromyxoid

The tumor matrix.

cells

were

embedded

within

partly

hyalinized

tumor cells withm a fibromyxoid matrix (Fig 7). No atypical features were present. Mitotic figures were infrequent. l-3 per 10 high power fields. The stroma was partly hyahnized, but no ossification was found in either the rim of the capsule or the tumor parenchyma (Fig 3). hmnunohistochemtcal stains showed marked nuclear and cytoplasmic positivity for S-100 and S-100 beta protein. Stain for vimentin was weakly positive and that of glial fibrillary acidic protein (GFAP) was focally posittve. Stams for S-100 alpha protein. cytokeratin, desmm. EMA. LCA, HMB-45. NSE, and MIC-2 were all negative. Ultrastructural exammations showed anastomosing clusters of neoplastic cells lamed by desmosomes with well-developed but discontinuous basal lamina (Fig 4) The stroma contamed abundant collagen fibers.

DISCUSSION

OFMT is a relatively new entity, first described by Enzinger et al in 1989, with a report of 59 cases.’ The number of reported cases have gradually increased over the years, accumulating to a little more than 100 cases in the world literature. Our case, a 6-year-old girl with a retroperitoneal OFMT with paraspinal extension. presented unique clinical features. Review of the literature (Table 1) showed this tumor to arise predominantly in

Fig 4. The tumor cells were head) with desmosome (single x7,300.)

lined by basal lamina arrowhead). (Original

(double arrowmagnification

extremity wall

1

Unknown (subcutaneous)

1 1

Akai et ai14

72

Upper

Oda et al6 Yoshida et aI12

30 54

Trunk Upper/lower

extremity

1 1

extremrty and neck (multiple) Donner15 Williams

et aIt6

Schofield et al3 (13 cases)

66 29-75 (53)

Upper extremity Head and neck

1 9

31-84(49)

Head and neck

5 3

Trunk Abdominal

wall

Buttock Upper extremity

(2) 5 1

Oda et al*

46

Presacrum tissue)

Murasawa et aIn Yang et aI’*

39 59

Head and neck Head and neck

1 1

Fisher et al* Fukunaga et al9

13 76

Abdominal Buttock

1 1

Kilpatrick et al4 (6 cases)

36-76 (57)

Barrett

et allo

Velasco-Pastor

et al”

(soft

(I)

wall

Upper/lower extremity

4

68

Buttock Back

2 1

43

Perianal

(subcutane-

1

ous) Nakayama et al7 Current case

65 6

Back Retroperrtoneum

1 1

with parasprnal extension

adult patients with a peak in the fifth decade. Four patients were under 20 years of age with the youngest reported case being a 13-year-old boy.2 The common site was subcutaneous tissue or muscle of upper or lower extremeties (53% of all reported cases) followed by the head and neck location (23%) and the trunk (23%). Twenty-two of 24 cases affecting the trunk were found in the subcutaneous regions, and the remaining 2 cases were unspecified.l-” To our knowledge, no patient under the age of 10 years or with deeply located tumor has been reported on so far. Regarding the age and location of the tumor in our patient, neuroblastoma, primitive neuroectodermal tumor (PNET), and extraskeletal Ewing’s sarcoma have been considered before operation. However, histopathologic features including the immunohistochern-

1296

IJlRl ET AL

cal staining and ultrastructural studies were typical of nonossifying variant of OFMT. Although tumors with ossification or peripheral rim of mature bone predominate, nonossifying variants are present in approximately 20% of the reported cases.2 Clinical manifestation and prognoses do not vary between the ossifying and nonossifying variants of OFMT. The tumor generally is considered a benign lesion, although local recurrence is quite common (27% in the original article by Enzinger et al). Two cases of OFMT with metastases showing extraskeleta1 osteosarcomalike pathological features1J2 and recent reports of six cases with atypical histopathologic findings, one of which metastasized to the lung,4 have aroused the possible potential for low-grade malignancy. The current case showed benign features; no significant cellular atypia, cellularity, or marked mitotic activity was

observed. The spinal portion of the tumor in our case was resected first, damaging the capsule and probably spilling some of its tumor cells systemically. Yet, without any adjuvant therapy, the patient is alive without recurrence 9 years after excision. Although reported cases have increased over the past few years, the nature of ossifying fibromyxoid tumor remains unclear. In our case, reactivity for S-100 and S-100 beta protein but negative S-100 alpha protein and presence of basal lamina surrounding interdigitating processes with abundant collagen fibers in the stroma were supportive of a nerve sheath tumor. In addition, surgically confirmed association of the tumor with a nerve and microscopically identified thick nerve fibers that closely attached to the tumor capsule, strongly suggested Schwannian origin of this tumor.

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1996

11. Velasco-Pastor AM, Escribano JM. Gil-Mateo MP, et al: Ossifying fibromyxotd tumor of soft parts. J Cutan Path01 23:381-384, 1996 12. Yoshida H. Minamizaki T, Yumoto T, et al: Ossifying fibromyxoid tumor of soft parts. Acta Path01 Jpn 41:1167-1170, 1991 13. Guamer I, Dominguez-Malagon HR. Meneses-Garcia A: Ossifying fibromyxoid tumor (letter, with author’s reply). Am J Surg Path01 14:1167-1170, 1990 14. Akai M, Axuma H, Ohno T, et al: Ossifying fibromyxoid tumor of soft parts of the upper arm. Skeletal Radio1 20:608-612, 1991 15. Donner LR: Ossifying fibromyxoid tumor of soft parts: Evidence supporting schwann cell origin. Hum Path01 23:200-202, 1992 16. Williams SB, Ellis GL, Meis JM, et al: Ossifying fibromyxoid tumor of soft parts of the head and neck: A clinicopathological and immunohistochemical study of nine cases. J Laryngol Otol 107:75-80. 1993 17. Murasawa S, Inayama Y, Nakatani Y, et al: A case of ossifying fibromixoid tumor of soft parts and review of the literature (in Japanese). Byon to Rmsho 13:255-263, 1995 18 Yang P, Hirose T, Hasegawa T. et al: Ossifying fibromyxoid tumor of soft parts: A morphological and immunohistochemical study. Path01 Intern 44:448-453. 1994