Bariatric Surgery Linked to Lower Risk of Female-Specific Cancers

A new study finds that bariatric surgery can have beneficial effects for women beyond just weight loss: it was also associated with lower risk of female-specific cancers, like breast or ovarian cancer.

The findings, published in Gynecologic Oncology, are the result of a prospective study that matched 1420 Swedish women who underwent bariatric surgery with 1447 women receiving conventional treatment for obesity. The women, who had a baseline body mass index (BMI) of at least 38 kg/m², were followed through the Swedish National Cancer Registry for a mean of 18.1 years to determine cancer risks.

Women who underwent bariatric surgery had a 29% lower risk of eventually experiencing any cancer than those who had not, (hazard ratio [HR], 0.71). About half of these cancer cases were female-specific, meaning incidences of breast, endometrial, ovarian, and other gynecological cancers. The bariatric surgery group’s risk of developing these cancers was reduced even further than the overall cancer risk, as HR for female-specific cancers was 0.68.

The researchers also found that the protective qualities of bariatric surgery against developing female-specific cancers were strongest in women with medium or high levels of baseline insulin. When analyzing the risk of individual cancer types, they determined that bariatric surgery significantly lowered the risk of developing endometrial cancer (HR, 0.56). The bariatric surgery group had lower rates of all female-specific cancers except cervical cancer, but these differences were not significant for cancers other than endometrial.

After adjusting for age, body mass index, and smoking status, the association between bariatric surgery and lower female-specific cancer risk persisted.

"The association between bariatric surgery and female-specific cancer is noteworthy as these comprised about half of the observed cancer events in our cohort and are common in the obese population," the researchers concluded.

In an editorial that accompanied the study, Peter A. Argenta, MD, of the University of Minnesota’s Division of Gynecologic Oncology, wondered if bariatric surgery could be “the next wave of cancer prevention” as the link between obesity and cancer risk becomes clearer. He cited other findings that have shown that weight loss after bariatric surgery can be linked to lower risks of health outcomes like mortality, diabetes, stroke, and heart attack.

However, bariatric surgery should not be regarded as a cure-all, Argenta wrote, considering the costs of the procedure and accompanying hospitalizations. Although these costs may be offset by reduced use of medications in later years, further studies should determine whether the surgery is associated with lower risk of cancer-related mortality or improved quality of life.