title: Comparison of tumor recurrence between laparoscopic total mesorectal excision with sphincter preservation and laparoscopic abdominoperineal resection for low rectal cancer.
abstract: BACKGROUND
  By traditional open surgery, the tumor recurrence rate of total mesorectal excision with sphincter-preserving procedure was lower than that of abdominoperineal resection (APR) for the treatment of low rectal cancer. The present study aimed to rescrutinize whether the same conclusion can be drawn when both surgical procedures are performed laparoscopically.
  
  
  METHODS
  We retrospectively reviewed the prospectively recorded clinicopathologic data of 344 consecutive patients with low rectal cancer, in which 170 patients underwent preoperative chemoradiotherapy followed by laparoscopic total mesorectal excision (TME), whereas 174 patients underwent laparoscopic TME directly without chemoradiotherapy. Such patients were further stratified according to the pathologic tumor, node, metastasis stage (stage II or III disease) and surgical strategy (APR or sphincter-preserving operation [SPO]). The surgical procedures are presented in supplemental videos. The disease-free survival, recurrence patterns, and functional recovery of patient groups stratified as appropriate were compared.
  
  
  RESULTS
  In patients who received preoperative chemoradiotherapy, the estimated recurrence rate were similar between laparoscopic TME with SPO and laparoscopic APR with 10.6%, 7 of 66, versus 18.5%, 5 of 27, in stage II disease (p = 0.811, log-rank test); and 19.3%, 11 of 57, versus 20%, 4 of 20, in stage III disease (p = 0.980). In patients without preoperative chemoradiotherapy, the recurrence rate was significantly higher in laparoscopic APR than in the laparoscopic TME with SPO group of patients with stage III disease (45%, 9 of 20, vs. 19.3%, 16 of 83, p = 0.025), whereas the recurrence rate of the two procedures was similar (21.4%, 3 of 14, vs. 17.5%, 10 of 57, p = 0.702) in stage II disease.
  
  
  CONCLUSIONS
  When low rectal cancer was operated on by laparoscopic approach, the poorer prognosis of APR compared to SPO was only observed in stage III patients without preoperative chemoradiotherapy.
authors.affiliation: Division of Colorectal Surgery, Department of Surgery, National Taiwan University Hospital, and College of Medicine, No. 7, Chung-Shan South Road, Taipei, Taiwan. jintung@ntu.edu.tw
authors.forename: Jin-Tung
authors.initials: JT
authors.lastname: Liang
authors.forename: Jason Chia-Hsien
authors.initials: JC
authors.lastname: Cheng
authors.forename: Kuo-Chin
authors.initials: KC
authors.lastname: Huang
authors.forename: Hong-Shiee
authors.initials: HS
authors.lastname: Lai
authors.forename: Chia-Tung
authors.initials: CT
authors.lastname: Sun
mesh_terms: D001003:Anal Canal / Q000601:surgery; D059248:Chemoradiotherapy; D003113:Colonoscopy; D003952:Diagnostic Imaging; D005260:Female; D006801:Humans; D010535:Laparoscopy / Q000379:methods*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D010502:Perineum / Q000601:surgery; D012004:Rectal Neoplasms / Q000473:pathology* / Q000601:surgery*; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome