Bone scan in ossifying fibromyxoid tumor of soft parts

Imaging findings of ossifying fibromyxoid tumor with histopathological correlation: A case report

Ossifying fibromyxoid tumor (OFMT) is a soft tissue tumor of uncertain lineage that most often arises in the extremities of adults. Imaging findings of this uncommon tumor are rare. We, herein, present a case of OFMT occurring in the left thigh of a 36-year-old male. Radiological examinations revealed a well-circumscribed subcutaneous mass with an incomplete shell of peripheral ossification, suggesting a benign condition. Following complete excision, the mass was histopathologically diagnosed as an OFMT. The patient demonstrated no evidence of local recurrence within 11 months of follow-up. We describe the clinicopathological and radiological features, and review the relevant literature.

Paraspinal malignant ossifying fibromyxoid tumor with spinal involvement

Ossifying fibromyxoid tumors (OFT), first described in 1989 by Enzinger et al., are rare lesions; malignant OFT (MOFT) are even rarer. We report a large recurrent paraspinal MOFT invading the spine and causing epidural compression in a 70-year-old male, despite prior debulking and radiotherapy. Paraspinal involvement of these tumors has been reported only twice before. We describe its imaging, pathology, and also review the pertinent literature.

Giant atypical ossifying fibromyxoid tumour of the calf

We present a case of giant atypical ossifying fibromyxoid tumour (OFMT) of soft tissue, occurring in the calf, in a 77-year-old woman. The patient presented with a history of bleeding ulcer over a calf lump that had been present for over 4 years. Clinical presentation, radiological features and histopathologic findings are described, and the relevant literature is reviewed.

Ossifying fibromyxoid tumor of the skin: A report of 2 cases with light microscopic, immunohistochemical, and electron microscopic characterization

Ossifying fibromyxoid tumor is a rare fibro-osseous neoplasm occurring predominantly in the subcutaneous tissue and/or skeletal muscle of the extremities. The immunohistochemical and ultrastructural studies in reported cases favor neural or Schwannian origin. To date, ossifying fibromyxoid tumor presenting as a primary skin tumor has not been described in the literature. Two cases of primary cutaneous ossifying fibromyxoid tumor with light microscopic, immunohistochemical, and ultrastructural characterization are presented. Our observations also support neural differentiation of these tumors.

Ossifying fibromyxoid tumor of soft parts: a clinicopathologic study of 70 cases with emphasis on atypical and malignant variants

The ossifying fibromyxoid tumor of soft parts (OFMT) is an uncommon soft tissue neoplasm of uncertain lineage. Approximately 100 cases of OFMT have been reported. Although the majority behave in a benign fashion, very rare tumors with histologic and clinical evidence of malignancy have been reported. Criteria for malignancy in OFMT have not as yet been defined. Seventy cases of OFMT were retrieved from our consultation archives and studied with respect to patient age and sex, tumor site and size, growth pattern, percentage of typical OFMT, cellularity and nuclear grade, mitotic figures (MF)/50 high power fields (HPF), atypical mitoses, necrosis, vascular invasion, and the presence of bone. Immunohistochemistry for pancytokeratin, S-100 protein, smooth muscle actin, desmin, and collagen II was performed on a subset of cases. Follow-up information was obtained from the submitting pathologists and clinicians. The Fisher exact test was used for statistical analysis. Patients (39 male, 31 female) ranged in age from 14 to 83 years (median 49 years). The tumors occurred primarily as subcutaneous or deeply seated masses in the trunk and proximal extremities and ranged from 1 to 14 cm (median 4.0 cm). The percentage of typical OFMT present in each case ranged from 0% to 100% (median 70%), and bone was present in 44 cases (63%). Mitotic activity ranged from 0 to 40 MF/50 HPF (median 2 MF/50 HPF), necrosis was present in 12 cases (17%), and vascular invasion was seen in 8 cases (11%). High cellularity or high nuclear grade was seen in 14 and 13 cases, respectively. Immunohistochemical results were as follows: S-100 protein (33 of 55, 60%), pancytokeratin (5 of 48, 10%), smooth muscle actin (2 of 44, 5%), desmin (5 of 39, 13%), and collagen II (1 of 26, 4%). Follow-up (51 cases, mean 54 months, median 36 months, range 5-151 months) showed local recurrences in nine patients and metastases in eight patients. Currently, 41 patients are disease free, 6 are alive with disease, 4 are dead of disease, and 1 died of other causes. The presence of high cellularity (p = 0.002), high nuclear grade (p = 0.001), or >2 MF/50 HPF (p = 0.004) were significantly associated with the development of metastatic disease and local recurrence. Infiltrative growth was also associated with increased risk of local recurrence (p = 0.03). We conclude that the histologic spectrum of OFMT is broader than previously appreciated, as many clinically benign cases display moderate cellularity, nuclear enlargement, or have identifiable mitotic figures. Our results strongly suggest that OFMT with 1) high nuclear grade or 2) high cellularity and mitotic activity of >2 MF/50 HPF should be regarded as sarcomas with significant potential for metastasis and untoward outcome ("malignant OFMT"). The remainder can be considered within the spectrum of OFMT, recognizing that even these lesions possess a risk, albeit very low, of metastasis. Consequently, OFMT should be considered tumors of intermediate malignancy. Their line of differentiation remains unclear, although we suggest they may belong to the category of translocation-associated sarcomas, not all of which recapitulate a normal line of differentiation.