Interstitial implant alone or in combination with external beam radiation therapy for intermediate-risk prostate cancer: a survey of practice patterns in the United States

Brachytherapy. 2007 Jan-Mar;6(1):2-8. doi: 10.1016/j.brachy.2006.09.004.


Purpose: This study is aimed at understanding and defining the current patterns of care with respect to prostate brachytherapy for patients with intermediate-risk localized disease in the combined academic and community setting.

Methods and materials: A nomogram-based survey was developed at the Seattle Prostate Institute defining the accepted criteria for intermediate-risk prostate cancer. Patients were defined as having intermediate-risk prostate cancer if they met one of the following criteria: prostate-specific antigen (PSA) >10 ng/dL, Gleason score (GS) > or = 7, or cT2b or cT2c disease. Additional potential predictive factors including perineural invasion (PNI), GS 3+4 vs. 4+3, and high-volume disease were included.

Results: In the absence of PNI, all of those surveyed would perform monotherapy for intermediate-risk patients, GS 7 (3+4) or PSA 10-20, with cT1c and <30% cores +. Up to 80% would perform monotherapy for patients with cT1c, GS 7 (4+3), and <30% cores +. Eighty to 90% of physicians would perform an implant alone with cT2a and either a PSA of 10-20 or GS of 7 (3+4) and <30% cores +. Fifty to 60% of those surveyed stated that they would treat a patient with cT2b disease, GS 7 (3+4), or PSA 11-20, with less than two-thirds of the biopsy cores positive in the absence of PNI.

Conclusions: This Patterns of Care (POC) study reveals that certain subsets of intermediate-risk localized prostate cancer patients are considered appropriate candidates for an interstitial implant alone.

MeSH terms

  • Biopsy, Needle
  • Brachytherapy
  • Humans
  • Iodine Radioisotopes / therapeutic use
  • Male
  • Neoplasm Invasiveness
  • Patient Selection
  • Practice Patterns, Physicians'*
  • Prostatic Neoplasms / pathology
  • Prostatic Neoplasms / radiotherapy*
  • Retrospective Studies
  • Risk
  • United States


  • Iodine Radioisotopes