title: Once-daily reirradiation for rectal cancer in patients who have received previous pelvic radiotherapy.
abstract: BACKGROUND
  The purpose of this study is to assess the efficacy and toxicity using once-daily reirradiation for patients with rectal cancer having received previous pelvic radiotherapy.
  
  
  METHODS
  Between June 1997 and June 2008, 56 patients were identified having received previous pelvic radiotherapy and received reirradiation for rectal cancer. Reirradiation intent was palliative in 43 patients, and preoperative/postoperative in 13 patients. Eighty per cent of patients received concurrent chemotherapy (n = 45).
  
  
  RESULTS
  The median dose-fractionation reirradiation schedule was 39.6 Gy in 22 fractions once daily (range 20-39.6 Gy), and the median cumulative radiation dose was 87.3 Gy. Seven patients experienced a grade 3 acute toxicity, with no grade 4 event. Fifty-one patients (91%) completed the treatment and five patients required a treatment break. The overall symptomatic response rate was 88% at three months post-reirradiation. There was one late effect of skin ulceration among patients reirradiated palliatively. Median overall survival was 39 months in patients undergoing radical surgery versus 15 months in patients reirradiated palliatively (P < 0.001).
  
  
  CONCLUSIONS
  Once-daily reirradiation to a total dose of ≤39.6 Gy is relatively safe in the treatment of patients with rectal cancer after previous pelvic radiotherapy. It is effective in symptom control and provides an additional option in management of local recurrence.
authors.affiliation: Department of Radiation Oncology, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia. mng@radoncvic.com.au
authors.forename: Michael K Y
authors.initials: MK
authors.lastname: Ng
authors.forename: Trevor
authors.initials: T
authors.lastname: Leong
authors.forename: Alexander G
authors.initials: AG
authors.lastname: Heriot
authors.forename: Samuel Y K
authors.initials: SY
authors.lastname: Ngan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015897:Comorbidity; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality* / Q000517:prevention & control / Q000532:radiotherapy*; D010388:Pelvis / Q000528:radiation effects; D011832:Radiation Injuries / Q000453:epidemiology*; D011879:Radiotherapy Dosage; D020266:Radiotherapy, Conformal / Q000401:mortality*; D012004:Rectal Neoplasms / Q000401:mortality* / Q000532:radiotherapy*; D012307:Risk Factors; D015996:Survival Rate; D016896:Treatment Outcome; D014739:Victoria / Q000453:epidemiology
keywords: previous radiotherapy; rectal cancer; recurrence; reirradiation