ABSTRACT
Cancer cachexia is a frequent complication of advanced cancer due to a metabolic syndrome that differs from malnutrition or starvation and is characterized by poor appetite, muscle wasting, and the failure to gain weight even when apparently adequate calories are provided. Cachexia can be present even in the absence of weight loss when there is concomitant muscle loss and increased body fat termed as sarcopenic obesity. Furthermore, cachexia can be obscured by obvious obesity, leading to excess mortality unless cachexia is detected by measuring lean body mass. Cachexia can be compounded by pre-existing muscle loss due to aging and sedentary lifestyle and can be exacerbated by cancer therapy. Muscle wasting, the central pathophysiological event in cachexia, is associated not only with reduced quality of life (QoL) but also markedly reduced tolerance to chemotherapy, radiation, and surgery with complicating infections due to impaired immune function. Many of the primary events driving cachexia and inflammation involve the central nervous system and anorexigenic factors. Inflammation-related anorexia in combination with a catabolic state predominates in cancer cachexia. In addition to active management of secondary causes of anorexia, the early treatment of cachexia should include nutritional support and therapy directed at inflammation-related metabolic changes using anti-inflammatory drugs and nutrients. Combining existing therapies into a multimodal approach and developing novel therapies through clinical and basic research will provide new opportunities to develop and establish supportive oncology to improve cancer patients’ QoL and tolerance to cancer therapy. This chapter will review advances in the understanding of the molecular biology of the brain, immune system, and muscle biology that have provided new avenues of research into potential approaches for the treatment of cachexia.
