title: Is adjuvant chemotherapy necessary for patients with pathological complete response after neoadjuvant chemoradiotherapy and radical surgery in locally advanced rectal cancer? Long-term analysis of 40 ypCR patients at a single center.
abstract: OBJECTIVE
  According to practice guidelines, adjuvant chemotherapy (ACT) is required for all patients with locally advanced rectal cancer who have received neoadjuvant chemoradiotherapy (NCRT) and total mesorectal excision (TME). The objective of this study was to determine whether ACT is necessary for patients achieving pathological complete response (pCR) after NCRT followed by surgery.
  
  
  METHODS
  By retrospectively reviewing a prospectively collected database in our single tertiary care center, 210 patients with locally advanced rectal cancer who underwent NCRT followed by TME were identified between February 2005 and August 2013. All patients achieving ypCR were enrolled in this study, in which who underwent ACT (chemo group) and who did not (non-chemo group) were compared in terms of local recurrence (LR) rate, 5-year disease-free survival (DFS) rate and overall survival (OS) rate.
  
  
  RESULTS
  Forty consecutive patients with ypCR were enrolled, 19 (47.5 %) in chemo group and 21 (52.5 %) in non-chemo group. After a median follow-up of 57 months, five patients developed systemic recurrences, with the 5y-DFS rate of 83.5 %. No LR occurred in the two groups. The 5y-DFS rates for patients in chemo group and non-chemo group was 90.9 and 76.0 %, respectively, showing no statistically significant difference (p = 0.142). Multivariate analysis showed that tumor grade was the only independent prognostic factor for 5y-DFS and 5y-OS.
  
  
  CONCLUSIONS
  Results of this study suggested that it may not be necessary for all rectal cancer patients with ypCR after NCRT and radical surgery to receive ACT. Prospective randomized trials are warranted to further determine the value of ACT for ypCR patients.
authors.affiliation: Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Dong Dan, Dong Cheng District, Beijing, 100730, China.
authors.forename: Jiaolin
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Dong Dan, Dong Cheng District, Beijing, 100730, China. qiuhzpumch@163.com.
authors.forename: Huizhong
authors.initials: H
authors.lastname: Qiu
authors.affiliation: Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Dong Dan, Dong Cheng District, Beijing, 100730, China.
authors.forename: Guole
authors.initials: G
authors.lastname: Lin
authors.affiliation: Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Dong Dan, Dong Cheng District, Beijing, 100730, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Xiao
authors.affiliation: Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Dong Dan, Dong Cheng District, Beijing, 100730, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Wu
authors.affiliation: Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Dong Dan, Dong Cheng District, Beijing, 100730, China.
authors.forename: Wenming
authors.initials: W
authors.lastname: Wu
authors.affiliation: Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Dong Dan, Dong Cheng District, Beijing, 100730, China.
authors.forename: Xiyu
authors.initials: X
authors.lastname: Sun
authors.affiliation: Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Dong Dan, Dong Cheng District, Beijing, 100730, China.
authors.forename: Junyang
authors.initials: J
authors.lastname: Lu
authors.affiliation: Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Dong Dan, Dong Cheng District, Beijing, 100730, China.
authors.forename: Guannan
authors.initials: G
authors.lastname: Zhang
authors.affiliation: Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Dong Dan, Dong Cheng District, Beijing, 100730, China.
authors.forename: Lai
authors.initials: L
authors.lastname: Xu
authors.affiliation: Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Dong Dan, Dong Cheng District, Beijing, 100730, China.
authors.forename: Yuchao
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D059248:Chemoradiotherapy; D017024:Chemotherapy, Adjuvant; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D012004:Rectal Neoplasms / Q000473:pathology* / Q000601:surgery / Q000628:therapy*; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
keywords: Adjuvant chemotherapy; Neoadjuvant chemoradiotherapy; Pathological complete response; Rectal cancer; Survival