Colorectal cancer (CRC) is still one of the most common types of cancer in the world, and the gut microbiome plays an important role in its development. The microbiome is involved in the carcinogenesis, formation and progression of CRC as well as its response to different systemic therapies. | Rebersek BMC Cancer 2021 21 1325 https s12885-021-09054-2 REVIEW Open Access Gut microbiome and its role in colorectal cancer Martina Rebersek1 2 Abstract Colorectal cancer CRC is still one of the most common types of cancer in the world and the gut microbiome plays an important role in its development. The microbiome is involved in the carcinogenesis formation and progression of CRC as well as its response to different systemic therapies. The composition of bacterial strains and the influence of geography race sex and diet on the composition of the microbiome serve as important information for screening early detection and prediction of the treatment outcome of CRC. Microbiome modulation is one of the most prospective new strategies in medicine to improve the health of indi- viduals. Therefore future research and clinical trials on the gut microbiome in oncology as well as in the treatment of CRC patients are warranted to determine the efficacy of systemic treatments for CRC minimize adverse effects and increase survival rates. Keywords Gut microbiome Colorectal cancer Prognostic and predictive biomarkers Modulation of gut microbiome Systemic treatment of CRC Background Only 10 to 15 of CRC cases are hereditary which Colorectal cancer CRC is the third most common type underlines an important role of the environment as a of cancer with almost 2 million new cases per year and factor that genetically and epigenetically influences the it is the second leading cause of cancer-related deaths development of CRC. In recent years increasing impor- worldwide 1 . CRC is also one of the most common can- tance in the development of CRC has also been attrib- cer types in Slovenia 2 . According to the Cancer Reg- uted to the gut microbiome. istry of Slovenia there were 1321 new cases of CRC in 2017 of which 790 cases were men and 531 cases were Novel classification of CRC and its connection with gut women 2 . In Slovenia the incidence of CRC has been microbiota
