title: Rectal cancer with complete clinical response after neoadjuvant chemoradiotherapy, surgery, or "watch and wait".
abstract: OBJECTIVE
  The purpose of this study was to compare the outcomes of patients treated with chemoradiotherapy with a complete clinical response followed by either a "watch and wait" strategy or a total mesorectal excision.
  
  
  METHODS
  This was an observational retrospective study from a single institute. Patients with locally advanced rectal cancer following chemoradiotherapy with a complete clinical response from January 1, 2007 to December 31, 2014 were included.
  
  
  RESULTS
  The study population consisted of 18 patients who opted for a "watch and wait" policy and 26 patients who underwent radical surgery after achieving a complete clinical response. Patients had no documented treatment complications under the watch and wait policy, while 13 patients who underwent radical surgery experienced significant morbidity. There were two local recurrences in the watch and wait group; both were treated with salvage resection and had no associated mortality. In the radical surgery group, 1 patient showed an incomplete pathologic response (ypT0N1), and the remaining 25 patients showed complete pathologic responses; 1 had a distant recurrence, which was managed non-operatively, and 2 patients died of unrelated causes. The 5-year overall survival rate and median disease-free survival time were 100% and 69.78 months in the watch and wait group and 92.30% and 89.04 months in the radical surgery group.
  
  
  CONCLUSIONS
  A watch and wait policy avoids the morbidity associated with radical surgery and preserves oncologic outcomes in our retrospective study from a single institute. It could be considered a therapeutic option in patients with locally advanced rectal cancer following chemoradiotherapy with a complete clinical response.
authors.affiliation: Division of Colon and Rectal Surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, No. 325, Cheng-Kung Rd, Sec 2, Neihu 114, Taipei, Taiwan, Republic of China.
authors.forename: Chien-Liang
authors.initials: CL
authors.lastname: Lai
authors.affiliation: Division of Clinical Pathology, Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, Republic of China.
authors.forename: Mei-Ju
authors.initials: MJ
authors.lastname: Lai
authors.affiliation: Division of Colon and Rectal Surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, No. 325, Cheng-Kung Rd, Sec 2, Neihu 114, Taipei, Taiwan, Republic of China.
authors.forename: Chang-Chieh
authors.initials: CC
authors.lastname: Wu
authors.affiliation: Division of Colon and Rectal Surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, No. 325, Cheng-Kung Rd, Sec 2, Neihu 114, Taipei, Taiwan, Republic of China.
authors.forename: Shu-Wen
authors.initials: SW
authors.lastname: Jao
authors.affiliation: Division of Colon and Rectal Surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, No. 325, Cheng-Kung Rd, Sec 2, Neihu 114, Taipei, Taiwan, Republic of China. dtdrummer@gmail.com.
authors.forename: Cheng-Wen
authors.initials: CW
authors.lastname: Hsiao
mesh_terms: D059248:Chemoradiotherapy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000628:therapy; D012004:Rectal Neoplasms / Q000401:mortality / Q000601:surgery / Q000628:therapy*; D012189:Retrospective Studies; D015996:Survival Rate; D057832:Watchful Waiting
keywords: Chemoradiotherapy; Complete clinical response; Rectal cancer; Watch and wait