The link between endometriosis and ovarian cancer risk

Endometriosis vs. ovarian cancer - what’s the difference?

Endometriosis and ovarian cancer are two distinct conditions that can both affect the ovaries and cause similar symptoms, such as pelvic pain and bloating. However, they have very different causes, progression, and risks.

Endometriosis occurs when tissue similar to the lining of the uterus grows outside the womb, often affecting the pelvis, ovaries, and other organs. These tissue growths respond to hormonal changes, leading to inflammation, pain, and scar tissue.

Ovarian cancer, on the other hand, occurs when abnormal cells in the ovary or fallopian tubes grow uncontrollably, forming a cancerous tumour.

Key Differences:

• Cause: Endometriosis is driven by hormonal changes, while ovarian cancer results from genetics or cellular abnormalities.
• Age group affected: Endometriosis usually develops in younger individuals, while ovarian cancer is most common in those over 50. It is important to be aware that women of any age may develop either condition.
• Growth pattern: Endometriosis involves benign (non-cancerous) tissue growth, whereas ovarian cancer involves malignant (cancerous) tumours that can spread to other areas.
• Long-term impact: Endometriosis can be a lifelong condition affecting fertility and quality of life, while ovarian cancer requires urgent medical treatment to prevent its progression.

While both conditions can be challenging to diagnose due to overlapping symptoms, they require different approaches to treatment and management. If you experience persistent symptoms, such as ongoing pain, bloating, or changes in bowel habits, it’s important to consult a doctor to explore possible causes.

The link between endometriosis and ovarian cancer

There is ongoing research into the relationship between endometriosis and ovarian cancer. While endometriosis itself is not cancer, women with endometriosis may have a slightly increased risk of developing certain types of ovarian cancer.

Does endometriosis increase the risk of developing ovarian cancer?

• Yes, women with endometriosis are at a slightly higher risk of developing ovarian cancer, but this risk is still considered low.

1.3% of the general female population will develop ovarian cancer, compared to less than 2% of women who have endometriosis, so the difference is negligible.

The majority of women who have endometriosis will not get ovarian cancer, and most of those who do are usually diagnosed at an earlier stage and therefore have much better outcomes.

Regular monitoring and check-ups with your healthcare provider can help manage this risk.

What to do if you have endometriosis and are concerned

If you’re worried, the best thing to do is speak to your doctor. They can assess your personal risk factors and help you decide if any further monitoring is needed. In the meantime, being aware of symptoms—such as persistent bloating, pelvic pain, or changes in appetite—can help with early detection, though these symptoms are common in many conditions and don’t necessarily mean cancer.

Lowering your risk of developing ovarian cancer

While no one can completely prevent cancer, there are steps that may help lower the risk:

• Hormonal treatments - Some medications used to manage endometriosis, such as certain contraceptives, may also reduce ovarian cancer risk. Find out more about reducing risk of ovarian cancer.
• A healthy lifestyle - Maintaining a balanced diet, regular physical activity, and avoiding smoking can support overall health.
• Surgery - In some cases, people with endometriosis who undergo surgery (such as hysterectomy or removal of the ovaries) may see a reduced risk, but this is a decision that should be carefully discussed with a doctor.

When to speak to your GP

You should book an appointment to speak to your doctor if:

• You notice persistent changes in your body, such as bloating, pain, or digestive issues.
• You have a family history of ovarian or related cancers, as this may affect your risk. You can use our hereditary cancer risk calculator to find out more about this.
• You feel unsure or anxious about your health - there’s no harm in getting reassurance or having any questions you have answered.

Can ovarian cancer be misdiagnosed as endometriosis?

Endometriosis and ovarian cancer share several symptoms. Both conditions can cause pelvic pain, bloating, painful periods, pain during sex, and bowel or urinary issues. As a result, distinguishing between them can be challenging.

Talking to your GP is key. Endometriosis is notoriously difficult to diagnose—on average, it takes around seven years for someone to receive a diagnosis in the UK. This is because symptoms vary widely from person to person, and there’s no simple test to confirm it.

Ovarian cancer can also be difficult to detect early because its symptoms - such as persistent bloating, abdominal pain, and changes in bowel habits - are often mistaken for less serious conditions like IBS (Irritable Bowel Syndrome) or hormonal changes. Find out more about diagnosing ovarian cancer.

Since both conditions can overlap in symptoms, it’s essential to track changes in your body and speak to a doctor if you experience symptoms that are:

• Persistent (lasting more than a few weeks)
• Worsening over time
• Interfering with daily life

If you have endometriosis and notice new or unusual symptoms - such as ongoing bloating that doesn’t go away, unexpected weight loss, or changes in appetite - let your doctor know. While these symptoms don’t necessarily mean cancer, it’s always best to rule out any underlying concerns.