Women with endometriosis four times more likely to develop ovarian cancer than those without, study finds

Women with endometriosis are four times more likely to develop ovarian cancer than those without, a new study has revealed.

For those with severe cases of the painful long-term condition, the risk of cancer jumped tenfold.

Endometriosis occurs when the uterine lining grows outside of the uterus itself, and affects one in ten women in the UK.

Prior research has suggested a link between endometriosis and ovarian cancer, but new findings from the University of Utah found particularly severe endometriosis can significantly raise the risk of the life-threatening disease.

Analysing more than 78,000 women with endometriosis, the study showed women suffering from more severe cases of the condition were up to 20 times more likely to develop ovarian cancer.

Endometriosis occurs when the uterine lining grows outside of the uterus itself, and affects one in ten women in the UK 

This is comparable to the risk of lung cancer that smokers face.

Experts say this is due to the fact that severe endometriosis can cause cysts to form in the ovaries, which can become cancerous. 

The study concluded women with any kind of endometriosis had a four-fold risk of developing ovarian cancer, compared to those who do not. 

Ovarian cancer is relatively rare in the UK, with just 7,500 new cases each year.

It can be notoriously difficult to diagnose in its early stages, however, due to many symptoms being associated with other, less serious illnesses. 

Roughly 4,000 women die a year from ovarian cancer.

Likewise, doctors also struggle to spot endometriosis. In the UK, patients, on average, wait more than eight years from the onset of their symptoms to get a diagnosis.

Ovarian cancer is relatively rare in the UK, with just 7,500 new cases each year (Stock image)

Patients with a diagnosis are often given contraceptive drugs, which helps reduce symptoms, or undergo surgery to have patches of endometriosis tissue cut away.

Dr Jennifer Doherty, a cancer researcher at the University of Utah and the study’s author, described the findings as ‘really important’.

‘This impacts clinical care for individuals with severe endometriosis, since they would benefit from counselling about ovarian cancer risk and prevention,’ she said.

‘The research will also lead to further studies to understand the mechanisms through which specific types of endometriosis cause different types of ovarian cancer.’