Endometriosis May Increase Ovarian Cancer Risk

Endometriosis is a common condition among women in the United States. While it can happen at any age, it affects more than 11% of women ages 15 to 44. Endometriosis is when tissue that is similar to the lining of the uterus grows outside of the uterus.

Endometriosis can be very painful. It can also lead to other health problems for women, including making it hard to get pregnant. Previous research has even found a link between endometriosis and ovarian cancer. Now, a new study helps to further support this link.

Women with endometriosis have 4 times greater risk of ovarian cancer

The study found that women with endometriosis have about 4 times greater risk of developing ovarian cancer compared to women without endometriosis. The risk was especially high for developing tumors classified as type I ovarian cancer. These cancers usually grow slowly and cause fewer symptoms. Type I ovarian cancers include:

• Low-grade serous carcinoma
• Clear cell carcinoma
• Mucinous carcinoma
• Endometrioid carcinoma

Sometimes endometriosis is severe. Two of the severe types are:

• Deep infiltrating endometriosis - when the tissue spreads to organs in the pelvic area.
• Ovarian endometriomas - dark, fluid-filled cysts found in the ovaries.

Women with these severe forms of endometriosis have an even higher risk for ovarian cancer. In fact, the study found that women with more severe forms have a nearly 10 times greater risk of developing ovarian cancer compared to women without endometriosis.

“This study firmly establishes a strong link between endometriosis severity and the risk of developing type I ovarian cancers,” said Lan Coffman, MD, PhD, American Society of Clinical Oncology (ASCO) expert and assistant professor of hematology-oncology at the University of Pittsburgh School of Medicine. “While endometriosis has long been linked to type I ovarian cancer, determining the risk associated with endometriosis location and severity is critically important to identify women at the highest risk for developing these cancers.”

It is important for women with endometriosis to talk with their doctors about their personal cancer risk and learn how to monitor for ovarian cancer symptoms.

Endometriosis vs. ovarian cancer symptoms

The most common symptom of endometriosis is pelvic pain. However, the condition can cause other symptoms, including:

• Lower back pain
• Pain during sex
• Pain when peeing or having a bowel movement
• Bleeding between periods
• Bloating, diarrhea, or constipation

Endometriosis and ovarian cancer symptoms can often be similar. However, endometriosis symptoms often get worse during menstrual cycles (the time of your period). Ovarian cancer symptoms may get worse over time, but usually don’t come and go in intensity like endometriosis.

If you have endometriosis, monitor your symptoms. It’s important to note whether they get worse or if new symptoms occur. If this happens, be sure to talk with your doctor so they can help address the problem.

Other symptoms of ovarian cancer to watch for include:

• Trouble eating
• Feeling like you have to pee more frequently
• Fatigue
• Changes in your period, such as heavier or more irregular bleeding

Knowing your ovarian cancer risk

Aside from endometriosis, several factors are known to increase the risk of ovarian cancer, including:

• Having gone through menopause
• Being overweight or obese
• Having your first child after age 35
• Never having a full-term pregnancy
• Taking hormone therapy after menopause
• Having a family history of ovarian cancer, breast cancer, or colorectal cancer
• Having a family cancer syndrome

If you have questions about endometriosis vs. cancer symptoms, talk with your doctor. They can help determine your personal cancer risk and share steps you can take to help monitor for symptoms and even prevent the disease.