Cancer cachexia is a
metabolic syndrome that can be present even in the absence of
weight loss ('precachexia').
Cachexia is often compounded by pre-existing muscle loss, and is exacerbated by
cancer therapy. Furthermore,
cachexia is frequently obscured by
obesity, leading to under-diagnosis and excess mortality. Muscle wasting (the signal event in
cachexia) is associated not only with reduced quality of life, but also markedly increased toxicity from
chemotherapy. Many of the primary events driving
cachexia are likely mediated via the central nervous system and include
inflammation-related
anorexia and hypoanabolism or hypercatabolism. Treatment of
cachexia should be initiated early. In addition to active management of secondary causes of
anorexia (such as
pain and
nausea),
therapy should target reduced food intake (
nutritional support),
inflammation-related metabolic change (anti-inflammatory drugs or nutrients) and reduced physical activity (resistance exercise). Advances in the understanding of the molecular biology of the brain, immune system and skeletal muscle have provided novel targets for the treatment of
cachexia. The combination of
therapies into a standard multimodal package coupled with the development of novel
therapeutics promises a new era in supportive oncology whereby quality of life and tolerance to
cancer therapy could be improved considerably.