title: Long-term outcome for very high-risk prostate cancer treated primarily with a triple modality approach to include permanent interstitial brachytherapy.
abstract: OBJECTIVE
  To evaluate outcome in the most unfavorable subset of high-risk prostate cancer patients treated with a combination of supplemental external beam radiation therapy (EBRT) and brachytherapy.
  
  
  METHODS
  Very high-risk prostate cancer was defined as follows: any Gleason score 10, Gleason score 8-9 with >50% of the biopsy cores positive for malignancy, Gleason score 8-9 with a prostate-specific antigen (PSA) >20ng/mL, any clinical stage T3, or any PSA >40ng/mL. One hundred thirty-one patients were identified who met the aforementioned criteria. The median followup was 6.6 years. One hundred twenty (91.6%) patients received supplemental EBRT and 100 (76.4%) received androgen deprivation therapy (median duration, 19.5 months; range, 4-36 months). The median postimplant day 0 D(90) (i.e., the minimum percentage of the prescription dose that covers the planning target volume) was 121.9% of prescription dose. Multiple clinical treatment and dosimetric parameters were evaluated for impact on the evaluated survival parameters.
  
  
  RESULTS
  The median pretreatment PSA and Gleason score were 11.0ng/mL and 8. One hundred ten (84%) patients had a Gleason score ≥8. At 9 and 12 years, the cause-specific survival, biochemical progression-free survival, and overall survival were 91.0% and 86.5%, 87.3% and 87.3%, and 70.5% and 60.5%, respectively. The most common cause of death was heart disease (22.2%) with deaths from nonprostate cancer (12.7%) and prostate cancer (8.3%) being less likely.
  
  
  CONCLUSIONS
  Permanent interstitial brachytherapy usually with supplemental EBRT and androgen deprivation therapy results in excellent biochemical control and cause-specific survival in the most unfavorable subset of high-risk prostate cancer patients. Death from diseases of the heart was more than twice as likely as death from prostate cancer.
authors.affiliation: Tacoma/Valley Radiation Oncology Centers, Tacoma, WA, USA.
authors.forename: Nathan
authors.initials: N
authors.lastname: Bittner
authors.forename: Gregory S
authors.initials: GS
authors.lastname: Merrick
authors.forename: Wayne M
authors.initials: WM
authors.lastname: Butler
authors.forename: Robert W
authors.initials: RW
authors.lastname: Galbreath
authors.forename: Jonathan
authors.initials: J
authors.lastname: Lief
authors.forename: Edward
authors.initials: E
authors.lastname: Adamovich
authors.forename: Kent E
authors.initials: KE
authors.lastname: Wallner
mesh_terms: D000368:Aged; D001918:Brachytherapy / Q000379:methods / Q000401:mortality*; D003131:Combined Modality Therapy / Q000379:methods / Q000401:mortality; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D015995:Prevalence; D011471:Prostatic Neoplasms / Q000401:mortality* / Q000532:radiotherapy*; D012307:Risk Factors; D016019:Survival Analysis; D015996:Survival Rate; D016896:Treatment Outcome; D014861:Washington / Q000453:epidemiology