title: [Comparison of pathologic and clinical characteristics of young and old patients with advanced rectal cancer after neoadjuvant radiotherapy].
abstract: OBJECTIVE
  To address the difference of pathologic and clinical characteristics of the young and the middle-aged and elderly patients with advanced rectal cancer after neoadjuvant radiotherapy.
  
  
  METHODS
  A total of 252 patients undergoing radical surgery from January 2000 to January 2005 were included in this study. The patients were divided into two groups according to the age at diagnosis:young-patient group (< 40 years) and old-patient group (≥ 40 years). The pathologic and clinical materials were collected and the oncologic outcome was compared between the two arms.
  
  
  RESULTS
  A total of 252 patients were included in this study, included 54 patients in young-patient group and 198 patients in old-patient group, respectively. There was no significant difference in gender, clinical stage and pretreatment serum carcinoembryonic antigen (CEA) between the two groups. However, the proportion of mucinous and signet-ring cell cancer was significantly higher in young-patient group (20.4% vs. 4.0%, P < 0.05), and furthermore, the proportion of pathologic stage later than IIIA was also significantly higher in the young-patient group (61.1% vs. 42.9%, P < 0.05). There was no significant difference in local recurrence rate between the patients who received neoadjuvant radiotherapy and those who did not in the young-patient group, whereas the difference was observed significant in the old-patient group (3.3% vs. 11.2%, P < 0.05). There was no significant difference in both the disease free survival and overall survival between the two arms (5y-DFS: 63.3% vs. 68.5%, P > 0.05; 5y-OS: 73.5% vs. 72.9%, P > 0.05).
  
  
  CONCLUSIONS
  Rectal cancer in young patients has poorer histologic differentiation and more advanced pathologic stage, but the long-term survival is similar to that in middle-aged and elderly patients. The local control effect of neoadjuvant radiotherapy on rectal cancer in young patients still need to be further investigated.
authors.affiliation: Department of Colorectal Surgery, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University School of Oncology, Beijing Cancer Hospital & Institute, Beijing 100142, China.
authors.forename: Chang-zheng
authors.initials: CZ
authors.lastname: Du
authors.forename: Ji-shui
authors.initials: JS
authors.lastname: Zhang
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.forename: Jun
authors.initials: J
authors.lastname: Zhao
authors.forename: Yi-fan
authors.initials: YF
authors.lastname: Peng
authors.forename: Yun-feng
authors.initials: YF
authors.lastname: Yao
authors.forename: Wei-cheng
authors.initials: WC
authors.lastname: Xue
authors.forename: Jin
authors.initials: J
authors.lastname: Gu
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011300:Preoperative Care; D011379:Prognosis; D018714:Radiotherapy, Adjuvant; D012004:Rectal Neoplasms / Q000473:pathology* / Q000532:radiotherapy