According to evidence reviewed in this week’s issue of The Journal of the American Medical Association, the sudden, dramatic, and important developments of immunotherapy for cancer seem to work much better in obese people.(1)
The immune system is in charge of protecting us from invasion by infectious agents. When it works right your immune system also monitors for and fights the genesis of cancer tumors. The hallmark of the immune system doing it’s job is inflammation. But sometimes the immune system is diseased and inflammation is not properly controlled and attacks the good guys as in the case of, for example, arthritis. Increased problematical inflammation is associated with old age and obesity. Also obesity is associated with an increased incidence and death from some kinds of cancer.
So it was a surprise when it was found that breakthrough new treatments of cancer that use manipulation of the immune system actually worked much better in obese people.
Traditional treatments for cancer, gruesome surgery and poisonous chemotherapy and burning radiation, are horrendous. They devastate the normal rest of your body. But immunotherapy has the potential to be the “magic bullet” that is selective against the cancer without harming normal tissues. These new immunotherapies for previously hopeless kinds of cancer like malignant melanoma, are proving very effective. But it is complicated as we see with immune diseases and serious and sometimes fatal toxic effects can and do occur. It is so far impossible to predict what’s going to happen in any individual person. Understanding the reasons for this surprise connection with obesity should help us make immunotherapy more predictable and even more amazing.
Immunology is probably even more complicated than the subject of obesity. Put the two together and oy vey.
Murphy WJ, Longo DL. The surprisingly positive association between obesity and cancer immunotherapy efficacy. JAMA.2019;321(13) 1247-8.