Cancer and Obesity Explored

November 3rd, 2011 by MorganDowney Leave a reply »

The Institute of Medicine’s National Cancer Policy Forum this week convened a two-day workshop, “The Role of Obesity in Cancer Survival and Recurrance.” So this is a good opportunity to re-visit the relationship between these two deadly diseases. Susan Gapstur of the American Cancer Society noted the growing list of cancers associated with obesity. For men, these include cancers of the colon, esophagus, kidney, colorectum, pancreas, gallbladder and liver. Women are affected by the same cancers as well as of the endometrium and postmenopausal breast cancer. Evidence is accumulating for an association with non-Hodgkin’s lymphoma, ovarian cancer in women and aggressive prostate in men. Obesity, she pointed out, is not the second (to tobacco) leading risk factor of cancer. Ominously, she pointed out we do not know what the health effects will be for the children now obesity who will obese for a lifetime.

Pamela J. Goodwin of the University of Toronto explored potential mechanisms in the progression to cancer including inflammation, adipokines, hyperinsulinemia, diabetes/diabetes drugs and sex steroids. She pointed to studies showing reductions in cancer risk with intentional weight loss of 20 pounds or more. Intentional weight loss and in… [Int J Obes Relat Metab Disord. 2003] – PubMed – NCBI and reduction in the relative risks of death and of cancer following bariatric surgery. Metabolic surgery and cancer: protective effects of b… [Cancer. 2011] – PubMed – NCBI.  Specifically, she showed the positive effect of intentional weight loss on breast cancer risk   Does intentional weight loss reduce canc… [Diabetes Obes Metab. 2011] – PubMed – NCBI and the impact of physical activity on improvements in insulin in breast cancer survivors Impact of a mixed strength and endurance exerci… [J Clin Oncol. 2008] – PubMed – NCBI.

Bruce Wolfe of the Oregon and Science University and a bariatric surgeon reminded the participants that the Swedish Obesity Study found the reduction in mortality after bariatric surgery was greater for cancer than for cardiovascular events Effects of bariatric surgery on mortality in Sw… [N Engl J Med. 2007] – PubMed – NCBI. In a Utah study, bariatric surgery reduced deaths from cancer by 60% compared to a 48% reduction in cardiovascular events. Long-term mortality after gastric bypass surgery. [N Engl J Med. 2007] – PubMed – NCBI

Rachel Ballard-Barbash of the National Cancer Institute, who has been a leader in exploring the obesity-cancer connection for many years, moved the discussion to look at the co-morbid conditions of obesity and their relationship to cancer mortality, including renal disease, congestive heart failure, cerebrovascular disease, citing A refined comorbidity measurement algorithm fo… [Ann Epidemiol. 2007] – PubMed – NCBI

Patricia Ganz of the UCLA Schools of Medicine picked up the point and explained that about half of all deaths of breast cancer survivors are due to causes other than breast cancer. She recommended prevention of weight gain and/or weight loss in those breast cancer survivors who are obese. 

Thomas Wadden described the non-surgical approaches to weight loss used in the Diabetes Prevention Program and the LOOK Ahead study and the contribution of intensive behavioral counseling to reduction in comorbid conditions associated with obesity

Some of the workshop’s presentations are on-line at Workshop on the Role of Obesity in Cancer Survival and Recurrence – Institute of Medicine. Watch that site for future information on a publication from the workshop.