Ovarian serous adenocarcinoma with anaplastic areas containing osteoclast-like multinucleated giant cells

Abstract

Ovarian tumors with osteoclast-like multinucleated giant cells are rarely encountered, and the existence of osteoclast-like giant cells in ovarian tumors may have no effect on the patients' prognosis. We report a patient with ovarian serous adenocarcinoma containing osteoclast-like multinucleated giant cells in the anaplastic areas of the tumor, who had a poor prognosis. A recurrent tumor showed the same anaplastic appearance as that of the primary tumor, with osteoclast-like giant cells. Forty-one percent of tumor cells were positive for MIB-1 (Ki-67) antigen, and many cells overexpressed p53 protein. However, the giant cells were negative for both antigens, which meant that they were non-cycling cells. The giant cells were also negative for epithelial and non-epithelial antigens. The multinucleated osteoclast-like giant cells, as well as mononucleated tumor cells around the giant cells, expressed p21 (WAF1/ClP1) protein. These findings suggest that the multinucleated osteoclast-like giant cells in this tumor originated from the p21-expressing mononuclear tumor cells. The coexistence of anaplastic foci with multinucleated giant cells in serous adenocarcinomas of the ovary may indicate a poor prognosis.