Case of pure ovarian squamous cell carcinoma resistant to combination chemotherapy with paclitaxel and carboplatin but responsive to monotherapy with weekly irinotecan.

Primary ovarian squamous cell carcinoma is uncommon, and the optimal treatment strategy for this disease has not yet been established. A 71-year-old woman diagnosed with FIGO stage IIb pure ovarian squamous cell carcinoma underwent cytoreductive surgery followed by combination chemotherapy with paclitaxel and carboplatin. After the second treatment course, a recurrent mass grew rapidly, and serum tumor maker levels increased. Monotherapy with weekly irinotecan was then instituted. This second-line chemotherapy was remarkably effective, and the patient subsequently underwent complete interval debulking surgery with a pathological complete response after the third treatment course. Weekly irinotecan is an effective choice for primary ovarian squamous cell carcinoma resistant to combination chemotherapy with paclitaxel and carboplatin.