Evaluation of Cancer Cachexia and Analysis of Gut Microbiota in Patients With Breast Cancer Receiving Home Care

Cancer cachexia is a multifactorial syndrome defined by an ongoing loss of skeletal muscle mass that cannot be fully reversed by conventional nutritional support and leads to a progressive functional impairment. Moreover, cachexia is characterized by involuntary weight loss, reduced food intake, systemic inflammation, and metabolic alteration. Its pathophysiology is characterized by a negative protein and energy balance driven by a variable combination of reduced food intake and abnormal metabolism. It is common in people with advanced cancer and is associated with lower quality of life, poorer functional status, and shorter survival. Cachexia syndrome can develop progressively through various stages - precachexia, cachexia, and refractory cachexia and its severity can be classified according to degree of depletion of energy stores and body protein in combination with degree of ongoing weight loss. Refractory cachexia, which is considered no longer reversible, represents a very advanced stage associated with progressive worsening of quality of life and severe hypercatabolism, with an expected survival of less than three months.

The Gut Microbiota (GM) is increasingly recognized as a possible factor involved in the development and progression of cancer cachexia. Alterations in the GM, often referred to as dysbiosis, may contribute to systemic inflammation, intestinal barrier dysfunction, altered nutrient metabolism, and loss of muscle mass. Previous studies have shown that people with cancer cachexia may have specific alterations in GM, including differences in the abundance of certain bacterial groups and lower production of anti-inflammatory metabolites such as short-chain fatty acids.

The association between alterations in the GM and the development of cancer cachexia suggests that modifying the GM to correct cachexia-related dysbiosis may lead to new integrative approaches for the management of this highly burdensome condition.

Recent studies suggest that Breast Cancer (BC) is associated with GM dysbiosis and that changes in GM composition and function may play a crucial role in tumor development and progression. In these studies, patients with BC frequently show a different GM composition compared with healthy individuals, including specific alterations in certain bacterial taxa and a reduction in microbial alpha diversity. However, limited data are available on the relationship between GM and cachexia in people with BC, especially among those receiving home-based supportive and palliative care.

Considering that BC is one of the most common cancers among women assisted by the home supportive and palliative care program, it is particularly important to identify strategies that may improve the quality of life of these patients. A simple and feasible option to support the nutritional and functional status of these particularly vulnerable patients could be probiotic supplementation. At present, to our knowledge, no studies have evaluated the effect of probiotic supplementation on cachexia status in patients with BC.