The long-term risk of cancer was reduced in women with severe obesity who got bariatric surgery compared to carefully matched patients who did not get bariatric surgery, according to new research published in the Annals of Surgery.
Obesity is a strong risk factor for many types of cancer. This study examined whether or not bariatric surgery affected the risk of developing cancer.
The results showed that bariatric surgery reduced the risk of cancer in women, particularly in obesity-associated cancers, including postmenopausal breast cancer, endometrial cancer, colon cancer, and pancreatic cancer.
About the Study
To study the relationship between bariatric surgery and cancer risk, researchers analyzed data from the Kaiser Permanente integrated health insurance and care delivery system.
The study included 22,198 patients (80% female and no history of cancer) who had bariatric surgery between 2005 and 2012 with follow-up through 2014 and 66,427 non-surgical patients who were well-matched for demographics (such as age, sex, study site) and clinical characteristics (such as body mass index, presence of diabetes and hypertension).
At a mean follow-up of 3-½ years, the researchers found that the risk of cancer was lower among women who had undergone bariatric surgery compared with matched nonsurgical patients during follow-up, as shown in the these results:
- 33% lower risk of developing any cancer
- 41% lower risk of developing obesity-associated cancers
- postmenopausal breast cancer, 52% lower risk
- endometrial cancer, 50% lower risk
- colon cancer, 41% lower risk
- pancreatic cancer, 54% lower risk
A similar risk reduction of cancer was not seen in men. Researchers explained that most men are more likely to die of prostate and lung cancer, types of cancer not associated with obesity.
Researchers state that more research is needed to better understand the specific mechanisms through which bariatric surgery lowers cancer risk.
Source: Bariatric Surgery and the Risk of Cancer in a Large Multisite Cohort, Annals of Surgery, Published online September 21, 2017.