title: Gastrointestinal toxicity of transperineal interstitial prostate brachytherapy.
abstract: OBJECTIVE
  To characterize the severity and time course of rectal toxicity following transperineal prostate brachytherapy using prospectively recorded data, and to determine factors associated with toxicity.
  
  
  METHODS
  One hundred thirty-four patients with prostate cancer treated with transperineal brachytherapy from 1997 to 1999 had rectal toxicity data available for analysis. Patients with Gleason score (GS) > 6, prostate-specific antigen (PSA) > 6, or stage > T2a were treated initially with external beam radiation therapy followed by brachytherapy boost; patients with none of these features were treated with brachytherapy alone. Both iodine-125 and palladium-103 sources were used, and loaded according to a modified Quimby distribution. At each follow-up, toxicity was recorded according to a modified RTOG gastrointestinal scale.
  
  
  RESULTS
  Thirty-nine percent of patients experienced gastrointestinal toxicity, mostly Grade 1. Median duration of symptoms was 6 months. Two patients experienced Grade 3 toxicity, both of whom had minimal symptoms until their 12-month follow-up. There was no Grade 4 or 5 toxicity. The addition of external beam radiation therapy (p = 0.003), higher clinical stage (p = 0.006), and Caucasian race (p = 0.01) were associated with increased incidence of toxicity.
  
  
  CONCLUSIONS
  Most patients with rectal toxicity have very mild symptoms. There is a small risk of severe late toxicity. External beam radiation, higher stage, and race are associated with toxicity.
authors: Department of Radiation Oncology, Duke University Medical Center, Box 3085, Durham, NC 27710, USA. kang@radonc.duke.edu
authors: Song K
authors: SK
authors: Kang
authors: Rachel H
authors: RH
authors: Chou
authors: Richard K
authors: RK
authors: Dodge
authors: Robert W
authors: RW
authors: Clough
authors: Hi-Sung L
authors: HS
authors: Kang
authors: Carol A
authors: CA
authors: Hahn
authors: Arthur W
authors: AW
authors: Whitehurst
authors: Niall J
authors: NJ
authors: Buckley
authors: Jay H
authors: JH
authors: Kim
authors: Raymond E
authors: RE
authors: Joyner
authors: Gustavo S
authors: GS
authors: Montana
authors: Sally S
authors: SS
authors: Ingram
authors: Mitchell S
authors: MS
authors: Anscher
mesh_terms: D000328:Adult; D000368:Aged; D001918:Brachytherapy / Q000009:adverse effects* / Q000379:methods; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D010165:Palladium / Q000627:therapeutic use; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000532:radiotherapy*; D011832:Radiation Injuries / Q000150:complications*; D011868:Radioisotopes / Q000627:therapeutic use; D012002:Rectal Diseases / Q000209:etiology*; D012044:Regression Analysis
chemical_list: D007457:Iodine Radioisotopes; D011868:Radioisotopes; D010165:Palladium; D017430:Prostate-Specific Antigen