Obesity and breast cancer: How bariatric surgery offers hope for risk reduction – Times of India

In India It is estimated that there are 135 million obese individuals. Obesity is associated with higher morbidity and mortality rates for many chronic diseases and is associated with a 20% to 40% increased risk for receptor-positive postmenopausal breast cancer.

Obesity and associated chronic inflammation were shown to facilitate breast cancer growth and metastasis. Leptin, adiponectin, estrogen, and several pro-inflammatory cytokines are involved in the development of obesity-driven Breast Cancer through the activation of multiple oncogenic and pro-inflammatory pathways.

In premenopausal women, ovaries are the major source of estrogen. However, the adipose tissue is the significant source of estrogen in postmenopausal women . Thus, circulating estrogen in postmenopausal women is directly correlated with body weight, which is thought to increase the risk of postmenopausal breast cancer.

The excess calories stored as triglycerides in adipocytes can lead to endoplasmic reticulum stress, adipose tissue fibrosis, and hypoxia, which result in adipocyte cell death and initiation of inflammatory immune responses.



Furthermore, recent evidence reported that obesity-driven changes in the intestinal flora microbiome promoted cancer incidence and progression. Gut microflora can affect IGF-1 and estrogen responses, estrogen-regulated metabolism, and estradiol production in obese patients.

The mitigation of body fat levels was positively associated with decreased circulating estrogen and inversely associated with the risk of estrogen-dependent Breast cancer in postmenopausal women.
Bariatric surgery is one of the few weight loss interventions where significant weight loss is sustained. It was found that 1 year after bariatric surgery, the average amount of weight loss among patients was 27% compared with 1% in matched nonsurgical patients.

It is proven that Bariatric surgery is associated with a lower risk of several types of cancer, including an approximate 40% reduced risk of postmenopausal breast cancer and a significantly lower risk of premenopausal breast cancer compared with carefully matched women with severe obesity who did not undergo bariatric surgery. This reduction in risk is most pronounced in postmenopausal ERpositive Cases and premenopausal ER-negative compared with women without bariatric surgery.

Bariatric surgery is associated with changes in the composition of the gut microbiome. Differences in gut microbial diversity have been associated with breast cancer, and thus changes in the gut microbiota contribute to reduced cancer risk after bariatric surgery.

As the prevalence of severe obesity continues to rise, Bariatric surgery offers one of the only ways to achieve significant weight loss with good weight maintenance rates which can be a strong risk reduction strategy for Breast cancer.

(Dr. Ashish Gautam, Senior Director Robotic and Laparoscopic Surgery, Max Super Speciality Hospital, Patparganj)