title: Long-term results of an RTOG Phase II trial (00-19) of external-beam radiation therapy combined with permanent source brachytherapy for intermediate-risk clinically localized adenocarcinoma of the prostate.
abstract: OBJECTIVE
  External-beam radiation therapy combined with low-doserate permanent brachytherapy are commonly used to treat men with localized prostate cancer. This Phase II trial was performed to document late gastrointestinal or genitourinary toxicity as well as biochemical control for this treatment in a multi-institutional cooperative group setting. This report defines the long-term results of this trial.
  
  
  METHODS
  All eligible patients received external-beam radiation (45 Gy in 25 fractions) followed 2-6 weeks later by a permanent iodine 125 implant of 108 Gy. Late toxicity was defined by the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer late radiation morbidity scoring scheme. Biochemical control was defined by the American Society for Therapeutic Radiology and Oncology (ASTRO) Consensus definition and the ASTRO Phoenix definition.
  
  
  RESULTS
  One hundred thirty-eight patients were enrolled from 20 institutions, and 131 were eligible. Median follow-up (living patients) was 8.2 years (range, 2.7-9.3 years). The 8-year estimate of late grade >3 genitourinary and/or gastrointestinal toxicity was 15%. The most common grade >3 toxicities were urinary frequency, dysuria, and proctitis. There were two grade 4 toxicities, both bladder necrosis, and no grade 5 toxicities. In addition, 42% of patients complained of grade 3 impotence (no erections) at 8 years. The 8-year estimate of biochemical failure was 18% and 21% by the Phoenix and ASTRO consensus definitions, respectively.
  
  
  CONCLUSIONS
  Biochemical control for this treatment seems durable with 8 years of follow-up and is similar to high-dose external beam radiation alone or brachytherapy alone. Late toxicity in this multi-institutional trial is higher than reports from similar cohorts of patients treated with high-dose external-beam radiation alone or permanent low-doserate brachytherapy alone, perhaps suggesting further attention to strategies that limit doses to normal structures or to unimodal radiotherapy techniques.
authors.affiliation: Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI, USA. clawton@mcw.edu
authors.forename: Colleen A
authors.initials: CA
authors.lastname: Lawton
authors.forename: Yan
authors.initials: Y
authors.lastname: Yan
authors.forename: W Robert
authors.initials: WR
authors.lastname: Lee
authors.forename: Michael
authors.initials: M
authors.lastname: Gillin
authors.forename: Selim
authors.initials: S
authors.lastname: Firat
authors.forename: Madhava
authors.initials: M
authors.lastname: Baikadi
authors.forename: Juanita
authors.initials: J
authors.lastname: Crook
authors.forename: Michael
authors.initials: M
authors.lastname: Kuettel
authors.forename: Gerald
authors.initials: G
authors.lastname: Morton
authors.forename: Howard
authors.initials: H
authors.lastname: Sandler
mesh_terms: D000230:Adenocarcinoma / Q000097:blood / Q000473:pathology* / Q000532:radiotherapy*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy / Q000009:adverse effects / Q000379:methods / Q000592:standards; D019583:Dose Fractionation, Radiation; D007172:Erectile Dysfunction / Q000209:etiology; D005500:Follow-Up Studies; D041981:Gastrointestinal Tract / Q000528:radiation effects; D006801:Humans; D007457:Iodine Radioisotopes / Q000009:adverse effects / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D058958:Organs at Risk / Q000528:radiation effects*; D011349:Proctitis / Q000209:etiology; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000473:pathology* / Q000532:radiotherapy*; D011832:Radiation Injuries / Q000150:complications*; D011878:Radiotherapy / Q000009:adverse effects / Q000379:methods; D012306:Risk; D014555:Urination Disorders / Q000209:etiology; D014566:Urogenital System / Q000528:radiation effects
chemical_list: D007457:Iodine Radioisotopes; D017430:Prostate-Specific Antigen