Giant primary ovarian fibrosarcoma: Case report and review of pitfalls
A 23 year old unmarried nulliparous female without any feminization or masculinization features presented with abdominal distension, intermittent pain abdomen and significant weight loss. Abdominal ultrasonography (USG) revealed a large, solid mass in the right adnexa. The contralateral ovary was normal. No lymph-node enlargement was detected. Other abdominal viscera were unremarkable. Significant ascites was present. Serum α–fetoprotein and chorionic gonadotropin levels were not raised.\nUSG guided aspiration yielded blood mixed material showing clusters of highly pleomorphic oval to spindle shaped cells with indistinct cell borders [] and atypical mitotic figures. A dissociated cell pattern was also observed at places [] along with few bizarre nuclei []. No evidence of irregular branching or papillary configuration was seen. Psammoma bodies were absent. No acinar pattern or intracytoplasmic mucin was noted. There was no picket fence appearance as seen in mucinous neoplasms or coffee bean shaped nuclei of granulosa cell tumors. Call-Exner bodies were not found. Absence of abundant clear cytoplasm ruled out dysgerminoma. A cytological diagnosis of primary pleomorphic/ spindle-shaped sarcoma, possibly high grade fibrosarcoma, was proposed. Histological confirmation was suggested after taking adequate sections to rule out any malignant epithelial components missed due to sampling error that may occur in aspirated malignant mixed mesodermal tumors. Peritoneal fluid cytology was non-contributory.\nFollowing surgical excision, grossly, the right ovary measured 25 × 17 × 12 cm with a smooth external surface []. Sectioning revealed a solid, firm, grayish mass containing areas of hemorrhage and cystic degeneration. Histologically, the tumor was composed of spindle cells arranged in sheets and intersecting fascicles creating a diffuse herringbone appearance. There was mild to moderate nuclear atypia with enlarged, hyperchromatic, and oblong pleomorphic nuclei with prominent nucleoli. The tumor diffusely involved the entire ovarian stroma with no normal structures remaining. No epithelial component could be identified even after thorough sectioning. A formal mitotic count was carried out on all representative sections of the tumor by recording number of mitotic figures in 50 consecutive high-power fields (HPF) and calculating the average per 10 HPF. The mitotic count varied from 10 to 12 per 10 HPF. These features, particularly the raised mitotic activity, were diagnostic of fibrosarcoma. This was the largest ovarian fibrosarcoma reported till date to the best of our knowledge. Reticulin stain showed fibers separating individual neoplastic cells. Immunohistochemical stains were positive for vimentin and CD34.