title: Feasibility of helical tomotherapy  for radical dose retreatment in pelvic area:  a report of 4 cases.
abstract: OBJECTIVE
  To retrospectively determine acute toxicity and local control in patients with recurrence after definitive radiotherapy for prostate, bladder and rectal carcinoma.
  
  
  METHODS
  Between September 2009 and March 2010, 4 patients with a prior history of pelvic radiotherapy were treated with helical tomotherapy. The prior course of radiotherapy was given for prostate cancer in 2 patients, bladder carcinoma in 1 patient and rectal carcinoma in 1 patient. The median prescribed dose of the prior course of radiotherapy was 6320 cGy (range, 5000-7600), and the median elapsed time between the first and second course was 17 months (range, 4-73). The total prescribed dose for tomotherapy retreatment was 60 Gy in 3 patients and 50 Gy in 1 patient. Hormone therapy was administered to 2 patients before and during radiation. No patient underwent surgical resection.
  
  
  RESULTS
  The cumulative mean dose to the rectum ranged from 3813 to 6058 cGy; cumulative rectal maximum dose to 1 cc ranged from 6475 to 8780 cGy. Regarding the bladder, the cumulative mean dose was between 4384 and 7612 cGy; cumulative maximum dose to 1 cc ranged from 7560 to 9790 cGy. All patients completed the re-irradiation course. Acute genitourinary toxicity (RTOG scale) was grade 0 in 3 patients and grade 1 in 1 patient; acute gastrointestinal toxicity was grade 0 in 3 patients and grade 1 in 1 patient. With a median follow-up of 9 months (range, 7-12), late toxicity was G0 in all patients. Three patients showed partial response with computed tomography or magnetic resonance imaging, and 1 had a PSA decrease.
  
  
  CONCLUSIONS
  Re-irradiation with helical tomotherapy was well tolerated, with low rates of acute and late toxicity. It can be therefore considered a useful tool to improve local control in patients previously treated with radiotherapy. However, a larger number of patients and a longer follow-up are required to assess retreatment safety.
authors: Department of Radaiation Oncology, National Institute of Cancer Research, Genoa, Italy. francesco.richchetti@istge.it
authors: Francesco
authors: F
authors: Ricchetti
authors: Salvina
authors: S
authors: Barra
authors: Stefano
authors: S
authors: Agostinelli
authors: Stefano
authors: S
authors: Vagge
authors: Michela
authors: M
authors: Marcenaro
authors: Renzo
authors: R
authors: Corvò
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017809:Fatal Outcome; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010386:Pelvic Neoplasms / Q000532:radiotherapy; D011471:Prostatic Neoplasms / Q000175:diagnosis / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D011881:Radiotherapy, Computer-Assisted; D012004:Rectal Neoplasms / Q000175:diagnosis / Q000532:radiotherapy*; D019233:Retreatment; D036542:Tomography, Spiral Computed / Q000009:adverse effects; D016896:Treatment Outcome; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis / Q000532:radiotherapy*