ENDOMETRIOSIS has been associated with an elevated risk of ovarian cancer. However, the associations between endometriosis subtypes and ovarian cancer histotypes remain unknown. The research team based at the Huntsman Cancer Institute, University of Utah, Salt Lake City, USA and the Boston University Chobanian & Avedisian School of Medicine, Massachusetts, USA, sought to evaluate the association between endometriosis subtypes and incidence of ovarian cancer.
Cases of endometriosis were identified using the Utah Population Database, an electronic health record, before being categorised as superficial endometriosis, ovarian endometriomas, deep infiltrating endometriosis, or other. Overall, 78,893 women with endometriosis were matched to women without endometriosis in a 1:5 ratio. Estimated adjusted hazard ratios (aHR); adjusted risk differences (aRD) per 10 000 women; and 95% confidence intervals (CI) for overall ovarian cancer, type I ovarian cancer, and type II ovarian cancer were recorded. Results were compared between women with each type of endometriosis and women without endometriosis, with sociodemographic factors, reproductive history, and past gynecologic operations accounted for.
Analysis showed the average age at first endometrial diagnosis was 36 years. Within the cohort, 597 women had ovarian cancer, and the risk for ovarian cancer was higher among women with endometriosis (aHR, 4.20; 95% CI, 3.59-4.91; aRD, 9.90; 95% CI, 7.22-12.57). The risk of type 1 ovarian cancer was especially high (aHR, 7.48; 95% CI, 5.80-9.65; aRD, 7.53; 95% CI, 5.46-9.61). The risk of ovarian cancer was highest amongst women with deep infiltrating endometriosis and/or ovarian endometriomas for all ovarian cancers, type 1 ovarian cancer, and type 2 ovarian cancer.
Overall, ovarian cancer risk was significantly increased among women with ovarian endometriomas and/or deep infiltrating endometriosis. The research team therefore suggest that this population may benefit from counseling regarding cancer risk and prevention. Furthermore, these results could inform targeted screening and prevention studies in the future.
Abigail Craig | EMJ
Reference
Barnard ME et al. Endometriosis Typology and Ovarian Cancer Risk. JAMA. 2024;doi.org/10.1001/jama.2024.9210.
