Weight loss surgery may prevent womb cancer in obese women

In a new study, researchers found that in women who had the gastric sleeve or bypass surgery for obesity, the precancerous tissue in their womb reverted to normal tissue when they lost weight.

Doctors have long known that womb cancer is caused by obesity, however, until now, the effect of losing weight on precancerous changes in the womb have been poorly studied.

Around 9,000 women a year are diagnosed with womb cancer, of which 2,300 women die. Pre-menopausal women treated for womb cancer by surgery lose the ability to have children.

In the study led by University of Manchester and Salford Royal scientists, 72 women with an average BMI of over 50—considered to be super obese—had biopsies taken from their wombs during gastric sleeve or bypass surgery.

Among the women, four were found to have womb cancer, which was treated by hysterectomy.

A further six patients had atypical endometrial hyperplasia, a precancerous condition that causes the overgrowth of cells in the womb.

Of the six women with endometrial hyperplasia, three had no signs of the condition when re-tested at eight weeks, after losing around three stone in weight.

The remaining three were treated by a Mirena coil, which releases the hormone progesterone into the womb and reverses precancerous changes.

Two were shown to be free of the condition after six months.

During six monthly checks over four years, the team found that the precancerous tissue did not return for these five women; the last had a hysterectomy.

The remaining 62 women had normal womb tissue at the time of weight loss surgery.

But it was high risk for an abnormality, with fast-growing cells, cancer-causing pathways switched on and cancer-stopping pathways switched off.

By twelve months after surgery, when the women had lost around seven stone in weight, the high-risk changes had reversed.

Obese postmenopausal women produce estrogen from their fat stores.

But as they no longer ovulate, the lack of progesterone allows the cells in the womb to grow – which increases the risk of cancer.

Inflammatory responses and Insulin production are also changed in obese women and can cause cells in the womb to grow.

The researchers suggest that because the reversal of precancerous changes in the womb was so quick, the metabolic consequences of weight loss surgery was crucial.

In their opinion, weight loss surgery is not an easy choice.

It changes the patient’s relationship with food forever because the patient will be eating smaller meals more frequently.

It is also important to remember that surgery can be a hazardous procedure.

That’s why it’s not for everyone: only about a third of women choose the surgical option.

But for those that choose it, gastric sleeve or bypass surgery can now be seen as a preventative measure for womb cancer.

Dr. Emma Crosbie, Clinical Senior Lecturer from The University of Manchester, led the study.

The research is published in the International Journal of Cancer.

Copyright © 2018 Knowridge Science Report. All rights reserved.

Source: International Journal of Cancer.