Primary Ovarian Carcinosarcoma: Cytological, Pathological, Immunocytochemical, and Immunohistochemical Features

Ovarian carcinosarcoma composed of high-grade carcinoma and sarcoma is an extremely rare neoplasm and typically occurs in postmenopausal women aged over 60 years. A 73-year-old female, gravida three para three, presented to our hospital with right lower abdominal pain. Right pelvic solid tumor with ascites was detected on pelvic ultrasound examination. She underwent hysterectomy, bilateral salpingo-oophorectomy and partial omentectomy, but the tumor had invaded to the right ureter, and some fragile tumor could not be taken (sub-optimal surgery). On the imprint and ascitic cytology specimens during operation, atypical cells suggestive of adenocarcinoma and spindle atypical cells with immunocytochemically vimentin positive were found. The resected tumor was histopathologically carcinosarcoma consisted of serous adenocarcinoma, chondrosarcoma and fibrosarcoma. Immunohistochemical analysis revealed that adenocarcinoma cells were positive for AE1/AE3 and fibrosarcoma cells stained with vimentin. The final diagnosis was the right ovarian carcinosarcoma (stage pT3CNxMx). Microsatellite instability was stable and BRCA1/2 mutations could not be found in the carcinosarcoma cells. The patient was given four cycles of chemotherapy with paclitaxel, carboplatin and bevacizumab regimen, and thereafter she was treated with the ifosfamide and cisplatin because of slight elevation of serum CA125.