A study published in the American Journal of Surgery found that bariatric surgery is associated with a reduced incidence and earlier stage of diagnosis of breast cancer in obese women.
Researchers conducted a literature review of Embase, Medline, Web of Science, and CINAHL for primary studies on female breast cancer incidence after bariatric surgery. A total of 11 studies were included in the final analysis, comprising 1,106,939 patients. In this cohort, 105,294 (9.5%) underwent bariatric surgery, and the other 1,001,645 were body mass index (BMI)-matched non-surgical controls. At baseline, the weighted mean BMI was similar for women in the bariatric surgery (44.8 kg/m2) and control (44.6 kg/m2) groups.
After a mean follow-up of 4.7 years in the bariatric surgery group and 2.7 years in the control group, 567 (0.54%) invasive breast cancer cases were diagnosed in the bariatric group versus 8,365 (0.84%) in the control group (risk ratio [RR], 0.50; 95% confidence interval [CI], 0.37-0.67).
Bariatric surgery was associated with an increased risk of stage I breast cancer (RR, 1.23; 95% CI, 1.06-1.44) and a reduced risk of stage III or IV breast cancer (RR, 0.50; 95% CI, 0.28-0.88). Hormone receptor characteristics were not affected, according to the researchers.
The researchers noted that the results of the study are based on surgeries performed between 2008 and 2013 and may not be representative of current bariatric surgery approaches.