Cancer cachexia is the prototypical example of comorbidity, occurring in most of cancer patients. It is a direct consequence of tumor growth and of the associated inflammatory/immune response.

Cachexia can be exacerbated by anti-cancer therapies, frequently resulting in dose limitation and/or treatment delay or discontinuation. The pathogenesis of cancer cachexia is still unclear and includes nutritional, metabolic, hormonal and immunological components.

Tumor ability to shape the immune response to its own advantage is now well accepted, while the possibility that such an altered immune response could play a role in the onset of cachexia is still an undefined issue. Indeed, most of the immune-related research on cachexia mainly focused on pro-inflammatory mediators, almost totally disregarding the interactions among immune cells and the homeostasis of peripheral tissues.

The present review provides an overview of the immune system dysregulations occurring in cancer cachexia, focusing on the possibility that immunomodulating strategies, mainly developed to stimulate the anti-cancer immune response, could be useful to counteract cachexia as well. Cancer and cachexia are frequent comorbidities of aging.

Along this line, cancer- and aging-associated muscle wasting likely coexist in the same patients. Since both conditions share some of the underlying mechanisms, the potential effectiveness of immunomodulation on sarcopenia of aging is discussed.