title: Phase II trial of short-course radiotherapy followed by delayed surgery for locoregionally advanced rectal cancer.
abstract: OBJECTIVE
  A prospective phase II study to investigate the feasibility and the rate of complete pathological response (ypT0) after short-course radiotherapy (SCRT) followed by surgery at 8 weeks.
  
  
  METHODS
  Operable patients with localized rectal cancer staged T3-4N0/+ or T2N+ were eligible and received 25 Gy (in one-third of patients, the gross tumor volume received a simultaneous integrated boost up to a total of 30 Gy) in five consecutive fractions to the posterior pelvis followed by surgery 8 weeks later. Pathological response and surgical toxicity were assessed in all patients.
  
  
  RESULTS
  Fifty-two patients (median age 68 years) completed the study. The median distance of the tumour from the anal verge was 6.5 cm. The median interval to surgery was 52 days. Three-quarters of patients underwent a low anterior resection. All underwent complete surgical resection and 100% had pathological negative margins. Ten per cent had stage ypT0 after radiotherapy. The median length of hospital stay was 8 days. Toxicity was comparable with the rates reported in the literature.
  
  
  CONCLUSIONS
  In this study, SCRT followed by delayed surgery was feasible and had acceptable toxicity. All patients underwent complete surgical resection and 100% had negative pathological margins. The rate of ypT0 was 10%.
authors.affiliation: Radiation Oncology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: S
authors.initials: S
authors.lastname: Faria
authors.forename: N
authors.initials: N
authors.lastname: Kopek
authors.forename: T
authors.initials: T
authors.lastname: Hijal
authors.forename: S
authors.initials: S
authors.lastname: Liberman
authors.forename: P
authors.initials: P
authors.lastname: Charlebois
authors.forename: B
authors.initials: B
authors.lastname: Stein
authors.forename: S
authors.initials: S
authors.lastname: Meterissian
authors.forename: A
authors.initials: A
authors.lastname: Meguerditchian
authors.forename: Z
authors.initials: Z
authors.lastname: Fawaz
authors.forename: G
authors.initials: G
authors.lastname: Artho
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy / Q000379:methods*; D011446:Prospective Studies; D018714:Radiotherapy, Adjuvant; D012004:Rectal Neoplasms / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D012007:Rectum / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome; D047368:Tumor Burden
keywords: neoajduvant treatment; radiotherapy; rectal cancer; short-course