ASCO: Link Between Obesity and Cancer

The American Society of Clinical Oncology (ASCO) issued a position statement on the link between obesity and cancer [J Clin Oncol. 2014; DOI:10.1200/JCO.2014.58.4680].

Obesity is “quickly overtaking tobacco as the leading preventable cause of cancer,” according to the statement. The position statement, which was led by Jennifer Ligibel, MD, Dana-Farber Cancer Institute, Boston, Massachusetts, is the first of its kind related to obesity from the ASCO organization.

The statement includes addressing the issue of public education and also outlines policies in research, clinical guidance, and advocacy, including proposed efforts to get reimbursement for obesity-related services for cancer patients.

However, there is no proof that weight loss improves survival in cancer patients. Nor is there evidence that weight loss prevents the development of cancer. There have never been randomized, controlled trials undertaken to test either of these fundamental concepts, acknowledged Dr. Ligibel.

Although, there are many studies of various lifestyle interventions, including weight loss, that show better outcomes and “concrete benefits” in cancer patients, according to Dr. Ligibel.

The statement lists some of these demonstrated benefits, which include:

• Less fatigue

• Better quality of life

• Better body image

• Lower incidence of comorbidity

• Favorable changes in biomarkers linked to cancer risk and prognosis

In addition, observational studies have shown that obesity is linked to an elevated risk for cancer, cancer recurrence, and cancer-related mortality in a number of cancers, according to the statement’s authors.

By 2030, it is estimated that almost half a million Americans will be diagnosed with obesity-related cancers annually, according to the ASCO press statement. The position of ASCO is that oncologists, or nurses, counselors, or other staff, should encourage patients to lose weight.

Additional clinical research on obesity and lifestyle interventions in cancer patients is also needed; ASCO noted that it is interested in getting this research organized.

The position statement also calls for a number of policy changes to increase access to obesity screening, diagnosis, and treatment. It highlights the need to close gaps in private and public insurance coverage for weight management services for both the general public and cancer patients.

ASCO is also calling for the Centers for Medicare & Medicaid Services to add obesity to the list of chronic diseases eligible for the proposed complex chronic care management services payments. Similarly, the statement also encourages the Department of Health and Human Services to clearly define access to obesity treatment services in the new state healthcare exchange plans under the Patient Protection and Affordable Care Act.

To address the statement, ASCO will host a summit on November 4 in Washington, DC, to bring together investigators from various disciplines, including medical oncology, nutrition, physical activity, and behavior medicine. The aim of the meeting will be to help prioritize research, ensure major questions are being addressed, and explore possible funding sources.—Kerri Fitzgerald