title: Phase II study of preoperative helical tomotherapy for rectal cancer.
abstract: OBJECTIVE
  To explore the efficacy and toxicity profile of helical tomotherapy in the preoperative treatment of patients with rectal cancer.
  
  
  METHODS
  Twenty-four patients with T3/T4 rectal cancer were included in this nonrandomized noncontrolled study. A dose of 46 Gy in daily fractions of 2 Gy was delivered to the presacral space and perineum if an abdominoperineal resection was deemed necessary. This dose was increased by a simultaneous integrated boost to 55.2 Gy when the circumferential resection margin was less than 2 mm on magnetic resonance imaging. Acute toxicity was evaluated weekly. Metabolic response was determined in the fifth week after the end of radiotherapy by means of fluorodeoxyglucose-positron emission tomography scan. A metabolic response was defined as a decrease in maximal standardized uptake value of more than 36%.
  
  
  RESULTS
  The mean volume of small bowel receiving more than 15 Gy and mean bladder dose were 227 ml and 20.8 Gy in the no-boost group and 141 ml and 21.5 Gy in the boost group. Only 1 patient developed Grade 3 enteritis. No other Grade 3 or 4 toxicities were observed. Two patients developed an anastomotic leak within 30 days after surgery. The metabolic response rate was 45% in the no-boost group compared with 77% in the boost group. All except 1 patient underwent an R0 resection.
  
  
  CONCLUSIONS
  Helical tomotherapy may decrease gastrointestinal toxicity in the preoperative radiotherapy of patients with rectal cancer. A simultaneous integrated radiation boost seems to result in a high metabolic response rate without excessive toxicity.
authors: Department of Radiation Oncology, Oncologisch Centrum UZ Brussel, Brussels, Belgium. mark.deridder@uzbrussel.be
authors: Mark
authors: M
authors: De Ridder
authors: Koen
authors: K
authors: Tournel
authors: Yves
authors: Y
authors: Van Nieuwenhove
authors: Benedikt
authors: B
authors: Engels
authors: Anne
authors: A
authors: Hoorens
authors: Hendrik
authors: H
authors: Everaert
authors: Bart
authors: B
authors: Op de Beeck
authors: Vincent
authors: V
authors: Vinh-Hung
authors: Jacques
authors: J
authors: De Grève
authors: Georges
authors: G
authors: Delvaux
authors: Dirk
authors: D
authors: Verellen
authors: Guy A
authors: GA
authors: Storme
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D011879:Radiotherapy Dosage; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects / Q000379:methods*; D012004:Rectal Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy* / Q000601:surgery; D036542:Tomography, Spiral Computed / Q000379:methods
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18