The Relationship Between Obesity and Cancer: Epidemiology, Pathophysiology, and the Effect of Obesity Treatment on Cancer

There is growing evidence relating to the risk of cancer in people with obesity. Obesity is already established as one of the strongest predisposing factors to cancer, and 'obesity-related' cancers have been defined in previous studies. In this review article, we examine the epidemiological relationship and describe the potential pathophysiological mechanisms that underpin the association between obesity and cancer. These include hormonal and growth factors that are in abundance in persons living with obesity and thereby increase cancer risk. Additionally, the increased disposition towards chronic inflammation in obesity also confers cancer risk. We also examine the impact of obesity on cancer treatment outcomes, focusing on surgery, chemotherapy, and immunotherapy. Conversely, we underline the impact of weight loss on cancer risk by examining different weight loss strategies.