The aim of this observational study is to retrospectively collect current survival data for 3995 primary rectal cancer patients who were extracted from 5097 rectal cancer patients admitted in Cancer Hospital, Chinese Academy of Medical Sciences from January 2000 to December 2010. Moreover, based on a Cox model, we want to develope a nomogram that predicts local recurrence, distant metastases, and survival for patients with rectal cancer treated with pre- or postoperative chemoradiotherapy (CRT).

Inclusion Criteria:

• Aged older than 18 years
• American Joint Committee on Cancer (six edition) stage I through IV disease
• Received either transabdominal resection, transanal excision, preoperative radiotherapy or chemoradiotherapy
• Had the histologic subtypes adenocarcinoma (not otherwise specified, mucinous or mucin-producing, mixed cell or with mixed subtypes, tubular, and papillary)

Exclusion Criteria:

• Had the histologic subtypes squamous cell carcinoma, carcinoid, neuroendocrine tumor, small cell carcinoma, leiomyosarcoma, sarcoma, gastrointestinal stromal sarcoma, melanoma, carcinosarcoma, rhabdoid tumors, or malignant peripheral nerve sheet tumors
• Only receive palliative surgery such as colostomy, sigmoidostomy
• Received palliative radiotherapy or chemoradiotherapy for metastatic disease
• With unresectable distant metastasis in liver, lung, bone, central nervous system , or peritoneal transplantation
• Had no detailed medical records

Clinical, pathological and routine laboratory characteristics for 3995 patients were extracted from 5097 patients with rectal cancer treated in Cancer Hospital, Chinese Academy of Medical Sciences from 2000 to 2010.The clinical data were reviewed and a prediction nomogram based on the Cox proportional hazards model were developed.