Painful womb condition endometriosis linked to higher risk of ovarian cancer
Women suffering from endometriosis three times more likely to develop the disease
A painful womb condition affecting two million British women has been linked to a greater risk of ovarian cancer.
Women suffering endometriosis are three times more likely to develop the disease, say researchers.
A study has identified three types of ovarian cancer which are more common in women with endometriosis, a condition that also affects fertility.
A study has identified three types of ovarian cancer which are more common in women with endometriosis, a condition that also affects fertility
The problem arises when cells normally found in the womb lining attach themselves to other parts of the pelvic area – causing scar tissue, pain and inflammation.
Experts say the lifetime risk of sufferers developing ovarian cancer remains small – increasing from one in 50 to one in 40, but women and doctors should be alert to symptoms.
The study from the Ovarian Cancer Association Consortium, based in New York, looked at data from about 23,000 women, including almost 8,000 with invasive ovarian cancer and 2,000 with borderline cancer.
They calculated the size of a link between endometriosis and five types of ovarian cancer. The researchers estimated that endometriosis is linked to a more than threefold chance of developing clear-cell ovarian cancers, and more than double the risk of developing endometrioid tumours.
The study, published in the Lancet Oncology journal, found no link with the most common form of the disease.
Lead author Celeste Leigh Pearce, from the University of Southern California, Los Angeles, said women at risk may benefit from early detection including screening. ‘Most women with endometriosis do not develop ovarian cancer. However, health care providers should be alert to the increased risk of specific subtypes of ovarian cancer in women with a history of endometriosis,’ she added.
Endometriosis (diagram pictured) causes the tissue that lines the womb to develop in the lower abdomen
Among theories for the higher risk is that the ovaries are exposed to hostile endometrium cells that invade the ovary during endometriosis. It is also possible that defects in the immune system which allow the endometriosis to grow might allow cancer cells to thrive elsewhere.
Endometriosis causes the tissue that lines the womb to develop in the lower abdomen. The tissue builds up on a monthly basis and breaks down as part of the menstrual cycle but because it is outside the womb, it cannot leave the body. Instead, it causes bleeding in the pelvis that leads to pain, lesions, scars and infertility.
The only reliable method of diagnosis is through surgery in which a tiny camera is inserted in the pelvic area.
There is no cure and treatments such as hormonal drugs and surgery have varying success and side effects.
Dr Paul Pharoah, reader in cancer epidemiology, at the University of Cambridge, said: ‘There are several types of ovarian cancer. This study shows for the first time that the increased risk associated with endometriosis is restricted to three of the less common types of common ovarian cancer.’
Shirley Hodgson, professor of cancer genetics, at St George’s University of London, said: ‘The implications for screening in women with endometriosis are difficult as screening for ovarian cancers by ultrasound scans and serum markers is not sufficiently sensitive to be used in this context.’
A spokesman for the charity Endometriosis UK said the risk of women with endometriosis developing ovarian cancer was extremely low but ovarian cancers were some of the biggest killers of women. ‘If you suspect that you may have an ovarian cancer, see a healthcare professional immediately,’ said the spokesman.