The Gut and Urinary Microbiota: A Rising Biomarker in Genitourinary Malignancies

The homeostasis and function of each human organ are associated with site-specific microbial communities (i.e., the microbiome). More importantly, microbial genes greatly outweigh human genes, indicating a profound influence by microbial communities and microbial metabolites on organ function, as well as hormone synthesis and xenobiotic turnover. Primarily for the gut-resident microbiome, several reports have associated dysbiosis (i.e., perturbance of the homeostatic microbiome) with the onset and progression of diseases, including several solid tumors, and with the efficacy of chemotherapy and immunotherapy. It is clear from these premises that the microbiome plays a central role in the management of cancer patients, including those with genitourinary neoplasias. In this chapter, we will review the current evidence of the contribution of the microbiome to tumor development and treatment in the genitourinary system.