Clear cell carcinoma of the ovary
Monika Przybyłkowska, Magdalena Kowalska, Grzegorz Gerulewicz, Beata Śpiewankiewicz
Ovarian clear cell carcinoma belongs to rather rare ovarian neoplasms and is believed to be a separate disease with a specific pathogenetic mechanism. It is diagnosed in women younger than 60 years of age, usually in early stages (FIGO I–II in 60% of cases). The National Comprehensive Cancer Network recommends surgical staging in early cancers and cytoreduction with adjuvant platinum- or taxane-based chemotherapy in later stages. Clear cell carcinoma of the ovary is characterized by worse response to chemotherapy and high carboplatin resistance. The mechanisms of its chemoresistance are unknown. The response to first-line chemotherapy is observed in only 11–27% of cases (vs. 73–81% for high grade carcinoma). Progression during chemotherapy is noted in 52% of patients (vs. 29% for high grade carcinoma). A relapse is associated with poor prognosis since it usually means considerable chemoresistance. Mean overall survival amounts to 25.3 months (vs. 42 months in epithelial ovarian carcinoma). Due to poor treatment outcomes in advanced stages of ovarian clear cell carcinoma, molecular targeted therapies are being developed. Research is being conducted in three directions: to develop new cytostatics, angiogenesis inhibitors and immunomodulators. Moreover, combinations of these drugs are also being investigated. It occurs that the future treatment is a therapy targeted to specifically impaired cell proliferation mechanisms in ovarian clear cell carcinoma. Moreover, the importance of adjuvant radiotherapy in stages FIGO IC–II must be emphasized.