Sarcopenia, body fat linked with mortality in nonmetastatic breast cancer

Obesity is highly prevalent among breast cancer survivors, and in addition to its effects on cancer development and outcomes, it also can affect treatment efficacy and adverse effects and complicate clinical management of breast cancer from obesity-related comorbidities such as hypertension and diabetes. As such, the American Society of Clinical Oncology made obesity and cancer one of their core priorities in 2013 and launched the Obesity & Cancer Initiative with activities ranging from education and awareness to clinical guidance, promotion of research, and policy and advocacy.

Despite its limitations, body mass index remains an easy tool to help health care clinicians identify patients at greater risk for poor outcomes and adverse effects and guide their recommendations, as well as to educate patients in self-assessing their weight status. Weight management and control are likely to have many benefits for breast cancer survivors but should always be tailored to individual patients’ needs. When CT imaging is available, the study by Caan et al. suggests that body composition measures can be useful in identifying women at higher risk of mortality. Their findings are an important reminder that weight loss and/or weight control programs must always incorporate physical activity with the goal of not just reducing adiposity, but also maintaining and increasing muscle mass, which would not only reduce the risk of death, but might also help improve quality of life after a cancer diagnosis.

Elisa V. Bandera, MD, PhD, is with the Rutgers Cancer Institute of New Jersey, Rutgers University, New Brunswick. Esther M. John, PhD, is with Stanford (Calif.) University. Both editorialists reported having no conflicts of interest to disclose. Their remarks are adapted from an accompanying invited commentary (JAMA Oncol. doi: 10.1001/jamaoncol.2018.0137).