Choice of the Optimal Treatment Strategies for Mid-low REctal Cancer

The purpose of this study is to compare the efficacy, prognosis, health economics of different treatment modalities of mid-low rectal cancer in different centers in China, and to conduct cost utility analysis (CUA) on the treatment process of rectal cancer to explore the best treatment modality that meets the actual need of medical units in each region and at each level. The investigators hope to provide evidence-based medical suggestions for medical quality control of rectal cancer and revision of clinical guidelines, and provides a source of decision making for medical management and medical insurance.