title: High-dose-rate brachytherapy as monotherapy delivered in two fractions within one day for favorable/intermediate-risk prostate cancer: preliminary toxicity data.
abstract: OBJECTIVE
  To report the toxicity profile of high-dose-rate (HDR)-brachytherapy (BT) as monotherapy in a Human Investigation Committee-approved study consisting of a single implant and two fractions (12 Gy × 2) for a total dose of 24 Gy, delivered within 1 day. The dose was subsequently increased to 27 Gy (13.5 Gy × 2) delivered in 1 day. We report the acute and early chronic genitourinary and gastrointestinal toxicity.
  
  
  METHODS
  A total of 173 patients were treated between December 2005 and July 2010. However, only the first 100 were part of the IRB-approved study and out of these, only 94 had a minimal follow-up of 6 months, representing the study population for this preliminary report. All patients had clinical Stage T2b or less (American Joint Committee on Cancer, 5th edition), Gleason score 6-7 (3+4), and prostate-specific antigen level of ≤12 ng/mL. Ultrasound-guided HDR-BT with real-time dosimetry was used. The prescription dose was 24 Gy for the first 50 patients and 27 Gy thereafter. The dosimetric goals and constraints were the same for the two dose groups. Toxicity was scored using the National Cancer Institute Common Terminology Criteria for Adverse Events, version 3. The highest toxicity scores encountered at any point during follow-up are reported.
  
  
  RESULTS
  The median follow-up was 17 months (range, 6-40.5). Most patients had Grade 0-1 acute toxicity. The Grade 2 acute genitourinary toxicity was mainly frequency/urgency (13%), dysuria (5%), hematuria, and dribbling/hesitancy (2%). None of the patients required a Foley catheter at any time; however, 8% of the patients experienced transient Grade 1 diarrhea. No other acute gastrointestinal toxicities were found. The most common chronic toxicity was Grade 2 urinary frequency/urgency in 16% of patients followed by dysuria in 4% of patients; 2 patients had Grade 2 rectal bleeding and 1 had Grade 4, requiring laser treatment.
  
  
  CONCLUSIONS
  Favorable-risk prostate cancer patients treated with a single implant HDR-BT to 24-27 Gy in two fractions within 1 day have excellent tolerance with minimal acute and chronic toxicity. Longer follow-up is needed to confirm these encouraging early results.
authors.affiliation: Department of Radiation Oncology, William Beaumont Hospital and Rose Cancer Institute, Royal Oak, Michigan 48073, USA. mghilezan@beaumont.edu
authors.forename: Michel
authors.initials: M
authors.lastname: Ghilezan
authors.forename: Alvaro
authors.initials: A
authors.lastname: Martinez
authors.forename: Gary
authors.initials: G
authors.lastname: Gustason
authors.forename: Daniel
authors.initials: D
authors.lastname: Krauss
authors.forename: J Vito
authors.initials: JV
authors.lastname: Antonucci
authors.forename: Peter
authors.initials: P
authors.lastname: Chen
authors.forename: James
authors.initials: J
authors.lastname: Fontanesi
authors.forename: Michelle
authors.initials: M
authors.lastname: Wallace
authors.forename: Hong
authors.initials: H
authors.lastname: Ye
authors.forename: Alyse
authors.initials: A
authors.lastname: Casey
authors.forename: Evelyn
authors.initials: E
authors.lastname: Sebastian
authors.forename: Leonard
authors.initials: L
authors.lastname: Kim
authors.forename: Amy
authors.initials: A
authors.lastname: Limbacher
mesh_terms: D000368:Aged; D001918:Brachytherapy / Q000009:adverse effects* / Q000379:methods; D003967:Diarrhea / Q000209:etiology*; D019583:Dose Fractionation, Radiation; D005500:Follow-Up Studies; D006471:Gastrointestinal Hemorrhage / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000473:pathology / Q000532:radiotherapy*; D012007:Rectum; D013997:Time Factors; D018084:Ultrasonography, Interventional; D014555:Urination Disorders / Q000209:etiology*
chemical_list: D017430:Prostate-Specific Antigen