Body composition and breast cancer - the role of lean body mass

Breast cancer risk and outcomes for breast cancer survivors are known to be influenced by body composition. A wealth of literature surrounds the function and role of fat tissue, however considerably less is known regarding lean body mass and its functional role in immune, hormonal and metabolic regulation in breast cancer aetiology. This review outlines findings relevant to lean body mass before, and following breast cancer diagnosis. A paucity of research exists regarding lean body mass and breast cancer risk. However, post-diagnosis lean body mass losses are commonly reported and a concern for ongoing co-morbidity after treatment. A comprehensive mechanism for sarcopenic obesity in breast cancer survivors is currently unknown. However, findings from other disease states indicate that the effects of chronic inflammation and/or an increase in sedentary activity may partly explain the exaggerated losses of lean body mass. Exercise has been a successful intervention for attenuating lean body mass losses after treatment, while weight loss through energy restriction may exacerbate breast cancer related sarcopenia. Combining exercise with dietary intervention to optimise lean body mass may be ideal; however there is insufficient evidence for this at present. Similarly, the role of functional food supplements, such as omega-3 fatty acids and essential amino acids, may aid lean body mass maintenance through anti-inflammatory action and increased muscle protein synthesis