Recurrent ovarian clear cell carcinoma: complete remission after radiation in combination with hyperthermia; a case study and in vitro study.

Since clear cell carcinoma of the ovary does not respond to conventional platinum-based chemotherapy, the prognosis of recurrent tumors is especially poor. In a 51-year old female who underwent surgery for clear cell carcinoma of the ovary, a solitary metastatic carcinoma developed in the pelvic cavity seven months after the initial surgery. The patient underwent a whole pelvic irradiation at a total dose of 65 Gy combined with hyperthermia. Complete remission was achieved 46 months after treatment. A study using gynecologic carcinoma cell lines showed that the mean 50% growth inhibitory dose of radiation was 1.2 +/- 0.4 Gy in several clear cell carcinoma cell lines. The value did not significantly differ from those for serous carcinoma cell lines (2.3 +/- 1.2 Gy) and uterine cervical carcinoma cell lines (1.6 +/- 0.4 Gy). Currently, no anticancer agents are effective for clear cell carcinoma. Radiotherapy combined with hyperthermia may be effective for localized tumors.