Having endometriosis can increase ovarian cancer risk 4.2-fold

Endometriosis has been linked to multiple health conditions and adverse health outcomes; however, a recent study in JAMA looked at endometriosis typology and ovarian cancer risk, concluding that having endometriosis was associated with a 4.2-fold greater risk of ovarian cancer.

The World Health Organization (WHO) defines endometriosis as a disease that causes abnormal tissue growth in the uterus and outside of the uterus, which can result in pain, chronic pelvic bleeding, heavy bleeding, infertility, bloating and nausea, fatigue, depression, and anxiety. The condition affects roughly 11% of reproductive-aged women, contributing to an estimated 50–60% of pelvic pain cases and up to 50% of female infertility cases.

Earlier studies found that endometriosis roughly doubled a woman’s risk of ovarian cancer; however, researchers in JAMA sought to understand how different subtypes of endometriosis impacted this risk.

Using data from the Utah Population Database, the researchers conducted a population-based cohort study that analyzed nearly 80,000 women. Approximately one-sixth of the participant population had endometriosis, while the remainder did not. Researchers assessed and compared ovarian cancer risks through adjusted hazard ratios.

Data from the study revealed that women with endometriosis were 4.2 times more likely to have ovarian cancer. Additionally, the risk of type I ovarian cancer was 7.48 times greater in women with endometriosis than women who did not have the condition.

A deeper analysis revealed that women with deep infiltrating endometriosis and/or ovarian endometriomas were at an even greater risk of ovarian cancer than women without endometriosis. For instance, they are 9.66 times more likely to get any type of ovarian cancer, 18.96 times more likely to get type I ovarian cancer, and 3.72 times more likely to get type II ovarian cancer.

“Studies that can better characterize the biology underlying these associations are urgently needed to guide improved ovarian cancer screening and prevention strategies among women with severe endometriosis, with or without other important ovarian cancer risk factors (e.g., BRCA1/2 variations) and to inform novel molecular targets for ovarian cancer treatments,” concluded researchers in the study.