title: Oncologic outcomes of primary and post-irradiated early stage rectal cancer: a retrospective cohort study.
abstract: OBJECTIVE
  To evaluate the oncologic outcomes of primary and post-irradiated early stage rectal cancer and the effectiveness of adjuvant chemotherapy for rectal cancer patients.
  
  
  METHODS
  Eighty-four patients with stage I rectal cancer after radical surgery were studied retrospectively and divided into ypstage I group (n = 45) and pstage I group (n = 39), according to their preoperative radiation, and compared by univariate and multivariate analysis.
  
  
  RESULTS
  The median follow-up time of patients was 70 mo. No significant difference was observed in disease progression between the two groups. The 5-year disease-free survival rate was 84.4% and 92.3%, respectively (P = 0.327) and the 5-year overall survival rate was 88.9% and 92.3%, respectively, for the two groups (P = 0.692). The disease progression was not significantly associated with the pretreatment clinical stage in ypstage I group. The 5-year disease progression rate was 10.5% and 19.2%, respectively, for the patients who received adjuvant chemotherapy and for those who rejected chemotherapy in the ypstage I group (P = 0.681).
  
  
  CONCLUSIONS
  The oncologic outcomes of primary and post-irradiated early stage rectal cancer are similar. Patients with ypstage I rectal cancer may slightly benefit from adjuvant chemotherapy.
authors.affiliation: Department of Colorectal Surgery, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University School of Oncology, Beijing Cancer Hospital and Institute, Beijing 100142, China.
authors.forename: Chang-Zheng
authors.initials: CZ
authors.lastname: Du
authors.forename: Yong-Chun
authors.initials: YC
authors.lastname: Chen
authors.forename: Yong
authors.initials: Y
authors.lastname: Cai
authors.forename: Wei-Cheng
authors.initials: WC
authors.lastname: Xue
authors.forename: Jin
authors.initials: J
authors.lastname: Gu
mesh_terms: D000368:Aged; D000970:Antineoplastic Agents / Q000494:pharmacology; D017024:Chemotherapy, Adjuvant / Q000379:methods; D015331:Cohort Studies; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008495:Medical Oncology / Q000379:methods; D008875:Middle Aged; D011379:Prognosis; D012004:Rectal Neoplasms / Q000532:radiotherapy* / Q000628:therapy*; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents