title: Analysis of acute toxicity with use of transabdominal ultrasonography for prostate positioning during intensity-modulated radiotherapy.
abstract: OBJECTIVE
  To analyze the effects of the B-mode ultrasound acquisition and targeting (BAT) system for positioning of patients with prostate cancer receiving intensity-modulated radiotherapy on acute gastrointestinal (GI) and genitourinary (GU) toxicity.
  
  
  METHODS
  The records of 50 consecutive patients treated using the BAT system were reviewed. Additionally, a comparison (no-BAT) group (ie, a group without a BAT study) treated in a similar manner was identified. The no-BAT group consisted of 49 patients treated immediately before the BAT group. For the two groups, the target definitions and dose prescriptions were identical, the treatment plan acceptance criteria were identical, and intensity-modulated radiotherapy was used for all patients. The daily BAT movements were charted in each of the three principal directions. Acute toxicity was scored for all patients according to the Radiation Therapy Oncology Group GI and GU acute toxicity scales.
  
  
  RESULTS
  The GU toxicity rates for the BAT versus no-BAT groups were grade 0 in 20% versus 14%; grade 1 in 38% versus 47%; grade 2 in 38% versus 39%; and grade 3 in 4% versus 0%, respectively (P = 0.284). The corresponding GI toxicity rates were grade 0 in 42% versus 27%; grade 1 in 28% versus 29%; and grade 2 in 30% versus 45% (P = 0.040). The incidence of GU and GI toxicity did not correlate with the directions or size of the BAT moves. Regression analysis revealed that for acute GI toxicity, the only variable reaching statistical significance was BAT use; no variable, including BAT use, reached statistical significance for acute GU toxicity.
  
  
  CONCLUSIONS
  The use of the BAT system did not change the rate of acute GU toxicity but did reduce the rate of acute GI toxicity.
authors.affiliation: Department of Radiation and Cellular Oncology, University of Chicago Hospitals, Chicago, Illinois 60637, USA. jani@rover.uchicago.edu
authors.forename: Ashesh B
authors.initials: AB
authors.lastname: Jani
authors.forename: John
authors.initials: J
authors.lastname: Gratzle
authors.forename: Emil
authors.initials: E
authors.lastname: Muresan
authors.forename: Karl
authors.initials: K
authors.lastname: Farrey
authors.forename: Mary K
authors.initials: MK
authors.lastname: Martel
mesh_terms: D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D004064:Digestive System / Q000000981:diagnostic imaging / Q000528:radiation effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging* / Q000532:radiotherapy*; D011832:Radiation Injuries / Q000000981:diagnostic imaging* / Q000209:etiology*; D014463:Ultrasonography; D014566:Urogenital System / Q000000981:diagnostic imaging / Q000528:radiation effects