Abstract

Metachronous papillary serous carcinoma of the peritoneum (PSCP) after endometrial carcinoma (EC) is an extremely rare condition. Only three patients have been reported in the English literature. We present the fourth patient who had a more aggressive and fatal clinical course. A 79-year-old multiparous woman complained of progressive abdominal pain and distension after 5 years, subsequent to total abdominal hysterectomy and bilateral salpingo-oophorectomy for endometrioid type EC. Serum CA-125 level being followed routinely rose above 500 IU/mL. Abdominal and pelvic computed tomography demonstrated ascites, omental thickening, and nodularity. Paracentesis showed malignant cells resembling papillary adenocarcinoma. Omentectomy and bilateral pelvic lymphadenectomy were performed as cytoreductive surgery. The histologic slides of the totally sampled ovaries obtained from the first operation were reexamined and the corresponding paraffin blocks were re-sectioned but no tumor was detected. The microscopic appearance of the tumor in the omentum differed from that of the previous EC. Immunohistochemically, while the tumor showed reactivity for low and high molecular weight cytokeratin (CK) cocktail, epithelial membrane antigen, CK7, CA-125, and Ber-EP4, the immunostains for calretinin, monoclonal carcinoembryonic antigen, and CK20 were negative. On the basis of these results and the criteria proposed by the Gynecologic Oncology Group, the tumor was diagnosed as metachronous PSCP developed after EC, which corresponded to stage IIIC according to FIGO criteria for ovarian carcinoma. The patient received two cycles of carboplatin and paclitaxel and died 2 months after the cytoreductive surgery