HomePhilippine Scientific Journalvol. 54 no. 1 (2021)

Sclerosing Epithelioid Fibrosarcoma in a 33-year-old Male: A Case Report

Gabriel A. Bumanglag | Azenith May H. Rafanan | Monica N. Yu-Tolentino | Janette S. Tolentino



Introduction. Sclerosing Epithelioid Fibrosarcoma (SEF) is a rare and distinctive deep-seated variant of fibrosarcoma that presents a major diagnostic challenge whose definitions are still being defined. The tumor occurs in any age group but most common among adults with the average age of forty-five. Due to the tumor’s rarity, epidemiological data is not well defined. Currently, there is one mentioned case of SEF in the local setting.1 This, therefore, shows the lack of locally published case reports. Case. We report a case of a 33-year-old male presenting with multiple soft tissue masses, predominantly in the inguinal and thoracic vertebral areas. Magnetic Resonance Imaging (MRI) of the left thigh showed an ovoid soft tissue mass measuring 5.6 x 3.6 x 4.9 cm and multiple smaller nodules noted in the muscles of both thighs. Computer tomography (CT) scan of the head, chest and abdomen showed an intradural extramedullary mass of level T11 and T12 vertebrae measuring 2.4 x 3.4 x 4.7 cm with spinal cord compression, along with multiple masses seen on the cerebral, subpleural, pulmonary, sacrum, gluteal, intrahepatic and pancreatic areas. Excision biopsies of the left inguinal and thoracic mass were performed. Histopathologic Findings. Gross findings showed tan-cream, firm to hard, ovoid tissues. Cut sections exhibited solid areas with hemorrhage and necrosis. Microsections disclosed a delineated to infiltrative subcutaneous neoplasm disposed in vague sheets and in nests variably surrounded by delicate to prominent sclerotic collagen. The individual neoplastic cells exhibited round to ovoid, vesicular to hyperchromatic nuclei, and sparse eosinophilic to clear cytoplasm. Mitosis was noted in 10/10 high power fields (HPFs). Foci of necrosis comprising 5-10% were noted. Immunohistochemistry staining (IHCs) showed strong reactivity to Epithelial Membrane Antigen (EMA) and CD99 with focal reactivity to CD34. There were no reactivity to S-100, Smooth Muscle Actin (SMA), STAT-6, ERG, Desmin and pan-Cytokeratin (CK). Ki-67 proliferation was 5-10%. Conclusion. Based on the available clinical data, imaging, histopathology and IHCs, the diagnosis of SEF was highly favored. This case was presented due to the tumor’s rarity and the scarcity of locally published case reports related to the tumor.


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