title: Preoperative radiotherapy improves survival for patients undergoing total mesorectal excision for stage T3 low rectal cancers.
abstract: OBJECTIVE
  To examine the effect of preoperative radiotherapy (PRT) on patients who undergo rectal resection with total mesorectal excision (TME) for stage T3 low rectal cancers.
  
  
  BACKGROUND
  Evidence for the value of PRT before rectal cancer surgery is weakened by variability in the use of TME. Many surgeons have concluded that PRT is unnecessary for small rectal tumors if TME is performed, but there are no prospective data to support this opinion.
  
  
  METHODS
  Since 1980, 2,200 patients with rectal cancer have been enrolled in a prospective database. Of these, 259 underwent curative anterior or abdominoperineal resection with TME for pathologically confirmed T3 lesions within 8 cm of the anal verge. Patients were grouped by receiving PRT (n = 92) or not receiving PRT (n = 167). Five-year overall survival and 5-year local recurrence rates were evaluated.
  
  
  RESULTS
  Overall survival was increased from 52% in patients not receiving PRT to 63% in those receiving PRT. PRT increased overall survival for node-negative patients from 58% to 82%, with no benefit for node-positive patients. There was no significant difference in local recurrence rates. When categorized by tumor size, there was no difference in overall survival or local recurrence for 0- to 2-cm tumors or those larger than 5 cm, but PRT increased overall survival from 50% to 72% for patients with 2- to 5-cm tumors. Similar results were observed for patients with tumors staged as T3 on preoperative endoluminal ultrasound.
  
  
  CONCLUSIONS
  Patients with pT3 low rectal cancers undergoing resection with TME have an improved survival with PRT. The effect is most beneficial for patients with node-negative and 2- to 5-cm tumors, although this group may include larger and node-positive tumors that have been downstaged by PRT. PRT should be advocated for all patients with T3 rectal cancers less than 8 cm from the anal verge, even if the surgery includes a properly performed TME.
authors.affiliation: Department of Colorectal Surgery, Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA. delanec@ccf.org
authors.forename: Conor P
authors.initials: CP
authors.lastname: Delaney
authors.forename: Ian C
authors.initials: IC
authors.lastname: Lavery
authors.forename: Antonio
authors.initials: A
authors.lastname: Brenner
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Hammel
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Senagore
authors.forename: Robert B
authors.initials: RB
authors.lastname: Noone
authors.forename: Victor W
authors.initials: VW
authors.lastname: Fazio
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003082:Colectomy / Q000379:methods*; D019160:Endosonography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D011300:Preoperative Care; D018714:Radiotherapy, Adjuvant; D012004:Rectal Neoplasms / Q000175:diagnosis / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery*; D012189:Retrospective Studies; D016019:Survival Analysis