Ovarian and extraovarian endometriosis-associated cancer

OBJECTIVE: To determine clinical characteristics of women with endometriosis-associated intraperitoneal cancers, to assess differences based on the relationship of the cancer to the endometriosis, and to assess factors associated with survival. METHODS: A search of medical records at The University of Texas M. D. Anderson Cancer Center from 1970 to 1999 identified patients who had synchronous endometriosis and intraperitoneal cancer. Demographic and clinicopathologic characteristics were evaluated for differences based on the relationship of the cancer to the endometriosis and for correlation with survival. RESULTS: One hundred fifteen patients were identified: 25 patients with ovarian cancer arising in endometriosis, 21 with an extraovarian cancer arising in endometriosis, 33 patients with endometriosis and ovarian cancer in the same location but without a definite transition point, and 36 patients with ovarian cancer and incidental endometriosis. Women with extraovarian cancers arising in endometriosis were more likely to be postmenopausal (P < .001) and use hormone replacement (P < .001). The median age was 47 years, the most common histological tumor types were clear cell and endometrioid (23% each), and the most common stage was stage I (31%). The median survival was 35 months. Univariate survival analysis revealed that gravidity (P < .038), grade (P < .001), stage (P < .001), histology (P < .01), and type of chemotherapy (P < .011) correlated with survival. Multivariable analysis revealed that stage and gravidity independently predicted survival. CONCLUSION: Women with endometriosis-associated cancers are typically premenopausal, have a high incidence of endometrioid and clear cell histologies, and have early stage disease. Stage and gravidity independently predicted survival.