Endometriosis and its treatment with danazol or lupron in relation to ovarian cancer.

PURPOSE It has been hypothesized that circulating androgens may be involved in the development of ovarian cancer. The androgenic medication, danazol, and the antiandrogenic medications, leuprolide and nafarelin, are commonly used in the treatment of endometriosis. We assessed the associations between the use of these medications and ovarian cancer. EXPERIMENTAL DESIGN We pooled information on self-reported use of danazol and leuprolide/nafarelin from two population-based case-control studies of incident ovarian cancer, comprising 1373 cases and 1980 controls. Odds ratios for the association between danazol and ovarian cancer, and leuprolide/nafarelin and ovarian cancer were adjusted for age, parity, oral contraceptive use, and family history of ovarian cancer. These analyses were repeated among the 120 cases and 124 controls who reported having had endometriosis. RESULTS Danazol users (n = 19) were at a significantly elevated 3.2 fold (95% confidence interval, 1.2-8.5) risk of developing ovarian cancer, whereas leuprolide/nafarelin users (n = 23) were not at significantly elevated risk (odds ratio, 1.0; 95% confidence interval, 0.4-2.4). Similar results were obtained among the subset of women with endometriosis. CONCLUSIONS Danazol, but not leuprolide/nafarelin, increased the risk of ovarian cancer. This supports the hypothesis that androgen excess may be associated with the development of ovarian cancer.