Anastomotic leakage is one of the most serious complications following colorectal surgery. Occurrence of anastomotic leakage is concealed and numerous risk factors might relate to anastomotic leakage, which greatly affect the postoperative outcomes and life quality of patients. Therefore, it is necessary to recognize risk factors to predict anastomotic leakage in advance and adopt available treatments to reduce the incidence. This review summarized the risk factors of postoperative anastomotic leakage base on two aspects, and so on. Perioperative related factors and biological markers, aiming to provide a theory for predicting anastomotic leakage then improving the treatment outcomes of colorectal cancer patients .

Gut microbiota plays an important role in the development of colorectal cancer, such as Fusobacterium Nucleatum, Peptostreptococcus and Streptococcus thermophilus. At present, Surgery is the mainly treatment strategy of colorectal cancer patients, supplemented by postoperative radiotherapy and chemotherapy. The influence of gut microbiota on colorectal cancer is not limited to the tumor itself. After tumor resection, gut microbiota is still in a state of disorder, which will affect the short-term and long-term prognosis of patients. Therefore, understanding the relationship between gut microbiota and prognosis of colorectal cancer is helpful to improve the prognosis of patients and reduce postoperative complications. In this review, the author will summarize the influence of gut microbiota on short-term and long-term prognosis of colorectal cancer patients.