Endometriosis itself is not cancer, but it does raise your risk of developing certain types

Endometriosis is a condition where tissue similar to the lining of your uterus grows outside the uterus, usually on your ovaries, fallopian tubes, or other pelvic organs. It is not cancer. However, people with endometriosis have a higher chance of developing ovarian cancer and, less commonly, other cancers compared to people without endometriosis.

The increased risk is real but still relatively small. Most people with endometriosis will never develop cancer. Understanding the connection helps you know what signs to watch for and when to talk to your doctor about screening or monitoring.

Key Takeaways

  • Endometriosis raises the risk of ovarian cancer, though most people with endometriosis do not develop it.
  • The risk appears highest for a specific type of ovarian cancer called clear cell or endometrioid carcinoma.
  • Chronic inflammation from endometriosis tissue may be one reason the cancer risk is higher.
  • Your doctor may recommend more frequent pelvic ultrasounds or blood tests if you have endometriosis and other risk factors for ovarian cancer.
  • Removing endometriosis tissue surgically may lower cancer risk, though this is still being studied.

Why endometriosis increases cancer risk

Endometriosis tissue behaves differently than normal uterine lining. It bleeds during your menstrual cycle but has no way to leave your body, so blood and tissue build up inside your pelvis. This creates a cycle of inflammation, scarring, and repeated injury to the tissue.

Over time, this chronic inflammation may damage the DNA in nearby cells, particularly in the ovaries. Damaged DNA can lead to cells growing abnormally and becoming cancerous. Additionally, endometriosis tissue itself sometimes undergoes changes that make it more likely to become cancerous, similar to how other chronic inflammatory conditions increase cancer risk elsewhere in the body.

Hormonal factors also play a role. Endometriosis tissue produces its own estrogen, which fuels both the endometriosis and potentially the growth of certain ovarian cancers. This is why some treatments for endometriosis focus on lowering estrogen levels.

Which cancers are linked to endometriosis

Ovarian cancer is the main cancer associated with endometriosis. The link is strongest for two specific types: clear cell carcinoma and endometrioid carcinoma. Together, these account for about 10 to 15 percent of ovarian cancers overall, but they appear more often in people with endometriosis.

Some research suggests a possible link between endometriosis and breast cancer, though this connection is weaker and less well established than the ovarian cancer link. A few studies have also looked at endometrial cancer (cancer of the uterine lining), but the evidence is mixed.

The bottom line is that ovarian cancer is the cancer most clearly linked to endometriosis. If you have endometriosis, your doctor will focus monitoring efforts there.

How much does endometriosis raise your cancer risk

The exact numbers vary depending on the study, but research generally shows that people with endometriosis have roughly two to three times the risk of ovarian cancer compared to people without endometriosis. This sounds significant, but it is important to put it in context.

Ovarian cancer is relatively uncommon. In the general population, the lifetime risk is about 1 in 78 for women. If endometriosis triples that risk, it becomes roughly 3 in 78, or about 4 percent. Most people with endometriosis still will not develop ovarian cancer. Risk also depends on other factors, including age, family history, and which type of endometriosis you have.

The risk appears to be higher if you have had endometriosis for many years or if you have had surgery to remove endometriosis tissue multiple times.

Screening and monitoring if you have endometriosis

There is no standard screening test for ovarian cancer that doctors recommend for all people with endometriosis. However, your doctor may suggest more frequent monitoring if you have endometriosis plus other risk factors, such as a family history of ovarian cancer or a genetic mutation like BRCA1 or BRCA2.

Monitoring typically involves a pelvic ultrasound and sometimes a blood test called CA-125. These are not perfect — they can miss some cancers and sometimes show false alarms — but they may catch problems earlier in people at higher risk. Talk with your doctor about whether monitoring makes sense for you based on your individual situation.

Some doctors also recommend that people with endometriosis pay attention to new or worsening symptoms. Ovarian cancer can cause bloating, pelvic pain, difficulty eating, and urinary urgency, though these symptoms are also common with endometriosis itself. If your symptoms change in a new way or do not improve with your usual endometriosis treatment, mention it to your doctor.

Treatment and cancer prevention

Treating endometriosis does not may provide cancer prevention, but it may lower your risk. Surgical removal of endometriosis tissue, particularly from the ovaries, eliminates the inflamed tissue that could potentially become cancerous. Hormonal treatments that suppress endometriosis — such as birth control pills, progestin-only methods, or GnRH agonists — may also reduce cancer risk by limiting the growth and inflammation of endometriosis tissue.

However, the research on whether treatment actually prevents cancer is still developing. No treatment has been proven to eliminate cancer risk entirely. The decision to treat endometriosis should be based primarily on managing your pain and symptoms, with cancer risk reduction as an additional benefit.

When to talk to your doctor

If you have endometriosis, mention it to your doctor at your regular visits. Your doctor can assess your individual risk based on your age, how long you have had endometriosis, your family history, and any genetic factors. Together, you can decide whether additional screening or monitoring is right for you.

Also tell your doctor if you notice new symptoms that do not fit your usual endometriosis pattern — for example, persistent bloating that does not come and go with your cycle, or pain that moves to a new location. These changes do not necessarily mean cancer, but they are worth investigating.

Frequently Asked Questions

Does endometriosis always turn into cancer?

No. Most people with endometriosis never develop cancer. While endometriosis does raise the risk of ovarian cancer, the absolute risk remains low. Many people live their entire lives with endometriosis and never face a cancer diagnosis.

Can endometriosis be removed to prevent cancer?

Surgery to remove endometriosis tissue may lower cancer risk, but it is not a may provide prevention. The decision to have surgery should be based mainly on treating your pain and symptoms. Talk with your doctor about whether surgery is right for your situation.

What symptoms of ovarian cancer should I watch for?

Ovarian cancer can cause bloating, pelvic or abdominal pain, difficulty eating, and urinary urgency. These symptoms overlap with endometriosis, so focus on changes: new symptoms, worsening symptoms, or symptoms that do not respond to your usual endometriosis treatment. Report any new pattern to your doctor.

Do I need genetic testing if I have endometriosis?

Genetic testing for BRCA mutations is not routine for everyone with endometriosis. However, if you have a family history of ovarian or breast cancer, or if you are under 50 and develop ovarian cancer, your doctor may recommend testing. Discuss your family history with your doctor to decide if testing makes sense for you.

Can birth control pills lower my cancer risk if I have endometriosis?

Birth control pills can help manage endometriosis symptoms and may reduce cancer risk by limiting the growth of endometriosis tissue. However, they are not a proven cancer prevention tool. The main reason to use them is symptom control. Discuss the benefits and risks with your doctor.