title: Clinical experience of SIB-IMRT in anal cancer and selective literature review.
abstract: OBJECTIVE
  To evaluate feasibility and outcome of our institutional SIB-IMRT schedule in patients with anal cancer and to selectively review the literature on different SIB-IMRT schedules.
  
  
  METHODS
  Between 01/08-06/13 25 patients with biopsy proven squamous cell anal cancer were treated in our institution with IMRT. Radiotherapy was delivered in two series using a SIB-IMRT schedule of 45 Gy/1.8 Gy to the primary tumor and adjacent pelvic lymph nodes and 38 Gy/1.52 Gy to elective nodes followed by an IMRT boost of 7×2 Gy = 14 Gy to the primary tumor and involved nodes (cumulative prescription dose: 59 Gy).
  
  
  RESULTS
  Mean follow-up was 20 months (range: 4-68). The 2-year-local control, colostomy-free survival, distant metastases-free survival and overall survival rates were 92%, 92%, 92%, and 88%, respectively. Grade 3 acute skin toxicity was observed in 6 patients (24%). No high grade gastrointestinal or urinary acute toxicity occurred. Four patients required more than one day of treatment interruption due to acute toxicity. No grade 3 or higher late sequelae were observed.
  
  
  CONCLUSIONS
  We present our institutional SIB-IMRT experience treating patients with anal cancer in two series using moderate single doses from 1.5-2.0 Gy. Our results, in terms of loco-regional outcome and toxicity, were comparable to other studies. The incidence of treatment interruptions was very low. Therefore this schedule appears to be safe for clinical use.
authors.forename: Stefan
authors.initials: S
authors.lastname: Janssen
authors.forename: Christoph
authors.initials: C
authors.lastname: Glanzmann
authors.forename: Peter
authors.initials: P
authors.lastname: Bauerfeind
authors.forename: Sonja
authors.initials: S
authors.lastname: Stieb
authors.forename: Gabriela
authors.initials: G
authors.lastname: Studer
authors.forename: Michelle
authors.initials: M
authors.lastname: Brown
authors.affiliation: Departments of Radiation Oncology, University Hospital Zurich, Rämistrasse 100, CH-8091 Zurich, Switzerland. oliver.riesterer@usz.ch.
authors.forename: Oliver
authors.initials: O
authors.lastname: Riesterer
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001005:Anus Neoplasms / Q000401:mortality / Q000532:radiotherapy*; D002294:Carcinoma, Squamous Cell / Q000401:mortality / Q000532:radiotherapy*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011879:Radiotherapy Dosage; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods*; D012189:Retrospective Studies; D016896:Treatment Outcome