Obesity Paradox in Lung Cancer Prognosis: Evolving Biological Insights and Clinical Implications

The survival rate of lung cancer remains low despite the progress of surgery and chemotherapy. With the increasing comorbidity of obesity in patients with lung cancer, new challenges are emerging in the management of this patient population. A key issue of interest is the prognostic effect of obesity on surgical and chemotherapeutic outcomes in patients with lung cancer, which is fueled by the growing observation of survival benefits in overweight or obese patients. This unexpected inverse relationship between obesity and lung cancer mortality, called the obesity paradox, remains poorly understood. The evolving insights into the heterogeneity of obesity phenotypes and associated biological connections with lung cancer progression in recent years may help explain some of the seemingly paradoxical relationship, and well-designed clinical studies looking at the causal role of obesity-associated molecules are expected. Here, we examine potential biological mechanisms behind the protective effects of obesity in lung cancer. We highlight the need to clarify the clinical implications of this relationship toward an updated intervention strategy in the clinical care of patients with lung cancer and obesity. (C) 2017 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.