Does endometriosis increase cancer risk?

Endometriosis affects at least one in 10 women. It causes painful periods and, in some cases, infertility.

But does it increase your cancer risk? We spoke with Aaron Shafer, M.D., associate professor of Gynecologic Oncology and Reproductive Medicine at the University of Texas MD Anderson Cancer Center, to learn more.

How do you know if you have endometriosis?

Symptoms of endometriosis include:

• Painful periods
• Pain during intercourse
• Excessive vaginal bleeding
• Infertility

Endometriosis is diagnosed with a pelvic exam, ultrasound or laparoscopy. If you’re concerned you have endometriosis, consult your physician.

What causes endometriosis?

This condition occurs when the tissue that normally lines the inside of the uterus grows outside of it. The exact cause of endometriosis is not known, but most theories center on how your cells, hormones and immune system works.

Does having endometriosis increase your ovarian cancer risk?

Given that endometriosis is related to how your cells and hormones work, it’s natural to think that it could be linked to cancer, but that’s not the case.

Having endometriosis doesn’t necessarily increase your cancer risk. There’s no research that links the two together. In fact, endometriosis doesn’t carry an increased risk for most other types of gynecological cancer, either. That includes endometrial cancer, despite the linked names.

And there’s no genetic trait associated with endometriosis that could lead to cancer.  

Some rare types of ovarian cancer, like clear cell ovarian cancer and endometrioid ovarian cancer, are more common in women with endometriosis. But even with those cancer types, the risk is still lower than 1%.

How do you treat endometriosis?

Depending on the severity of the symptoms and the patient’s goals, endometriosis can be treated with medications or surgery. Often hormonal contraceptives like birth control pills, patches and vaginal rings can help control the hormones responsible for the buildup of endometrial tissue each month.

Not only does this ease the pain caused by endometriosis, but it can also help lower your ovarian cancer risk. Anything that stops ovulation for a time can help lower your ovarian cancer risk because the less you ovulate, the less hormones you’re exposed to.

In some cases, birth control pills may increase your risk for breast cancer slightly, so talk to your doctor, if you’re concerned.

What else should women with endometriosis know?

Women with endometriosis don’t need to worry about an increased cancer risk. Instead, they should simply focus on treating their endometriosis and alleviating their symptoms.