American Society of Clinical Oncology Position Statement on Obesity and Cancer

Abstract

Rates of obesity have increased significantly over the last three decades in the United States and globally. In addition to contributing to heart disease and diabetes, obesity is a major unrecognized risk factor for cancer. Obesity is associated with worsened prognosis after cancer diagnosis and also negatively affects the delivery of systemic therapy, contributes to morbidity of cancer treatment, and may raise the risk of second malignancies and comorbidities. Research shows that the time after a cancer diagnosis can serve as a teachable moment to motivate individuals to adopt risk-reducing behaviors. For this reason, the oncology care team—the providers with whom a patient has the closest relationships in the critical period after a cancer diagnosis—is in a unique position to help patients lose weight and make other healthy lifestyle changes. The American Society of Clinical Oncology is committed to reducing the impact of obesity on cancer and has established a multipronged initiative to accomplish this goal by 1) increasing education and awareness of the evidence linking obesity and cancer; 2) providing tools and resources to help oncology providers address obesity with their patients; 3) building and fostering a robust research agenda to better understand the pathophysiology of energy balance alterations, evaluate the impact of behavior change on cancer outcomes, and determine the best methods to help cancer survivors make effective and useful changes in lifestyle behaviors; and 4) advocating for policy and systems change to address societal factors contributing to obesity and improve access to weight management services for patients with cancer.

Energy balance and fitness in adult survivors of childhood acute lymphoblastic leukemia

“…36 Clinicians who care for these survivors should provide counseling and, where appropriate, referral for intervention to help achieve a healthy weight. 37 Our study clearly documents that fitness deficits remain a problem for long-term survivors of childhood ALL, even when they are not exposed to CRT. In our cohort, proximal muscle strength and exercise capacity were impaired in ALL survivors, even among survivors who were not exposed to CRT.…”

“…In our cohort, proximal muscle strength and exercise capacity were impaired in ALL survivors, even among survivors who were not exposed to CRT. Jarvela et al 5 reported deficits in muscle performance and a 14% deficit in peak VO 2 when comparing 21 ALL survivors 16 to 30 years of age to age-and sex-matched controls, and Hartman et al 37 reported that mean performance on the 6-minute walk test was 2 SD below predicted, 5 years after therapy among 34 ALL survivors aged 9 to 18 years. In contrast, Taskinen et al 38 reported no differences in performance on 6 timed measures of physical fitness when comparing 45 ALL survivors aged 9 to 20 years to established reference values.…”

Cardiotoxicity From Human Epidermal Growth Factor Receptor‐2 (HER2) Targeted Therapies

“…Weight gain is common following the diagnosis of breast cancer and associated with poor outcomes 100. Counseling on weight loss, avoidance of weight gain, and routine physical activity may have a particularly important role in this population.…”

Obesity and Risk of Cancer: An Introductory Overview

“…In the past decade, it became more and more evident that obesity is also a risk factor for certain types of cancer [3]. In addition, more and more studies suggest that obesity may also increase the risk of poor prognosis for patients with certain cancers [4]. Cancer has traditionally primarily been viewed as a disorder of proliferation but has today been suggested to be also considered as a metabolic disease [5,6].…”