title: First 100 cases at a low volume prostate brachytherapy institution: learning curve and the importance of continuous quality improvement.
abstract: BACKGROUND
  We report the first 100 patients who underwent prostate brachytherapy as monotherapy with 125I at an institution with moderate volume radical prostatectomy but low volume brachytherapy (<2 cases per month). Learning curve and quality improvement was assessed by way of achieving prescription dose targets.
  
  
  METHODS
  From May 2002 to August 2006, 100 patients underwent prostate 125I brachytherapy monotherapy via preplanned approach. Preoperative planned dose to 100% of prostate gland (D100) was 145 Gy and postoperative confirmed dose was assessed by computed tomography. The cohort was divided into quartiles and recurrence was assessed using Kaplan-Meier analysis.
  
  
  RESULTS
  Patient quartiles were of similar age and Gleason grade, while PSA was slightly higher in the first group. Postoperative D90 increased after the first quartile (p = < 0.0001) reaching targeted values. Kaplan-Meier survival analysis revealed that 5 year recurrence-free survivals by Phoenix definition was 96%-100% in all groups while by ASTRO definition there was a decrease in recurrence for later cases.
  
  
  CONCLUSIONS
  At our low volume institution during the first 100 brachytherapy cases, a learning curve for radiation dosimetry was evident, which improved after 25 patients. Preplanned dose-volume parameters were adjusted, enabling the achievement of post-implant goals emphasizing the importance of continuous quality improvement. Although recurrence data is limited by sample size and moderate follow up, there was a discrepancy between the Phoenix and ASTRO definition when evaluating recurrence.
authors.affiliation: University of Iowa, Iowa City, Iowa, USA.
authors.forename: Nathan A
authors.initials: NA
authors.lastname: Bockholt
authors.forename: Eric M
authors.initials: EM
authors.lastname: DeRoo
authors.forename: Kenneth G
authors.initials: KG
authors.lastname: Nepple
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Modrick
authors.forename: Mark C
authors.initials: MC
authors.lastname: Smith
authors.forename: Bernard
authors.initials: B
authors.lastname: Fallon
authors.forename: A Curtis
authors.initials: AC
authors.lastname: Hass
authors.forename: Chad R
authors.initials: CR
authors.lastname: Tracy
authors.forename: James A
authors.initials: JA
authors.lastname: Brown
mesh_terms: D000368:Aged; D001918:Brachytherapy / Q000379:methods*; D015331:Cohort Studies; D004307:Dose-Response Relationship, Radiation; D061846:Hospitals, Low-Volume / Q000639:trends*; D006801:Humans; D053208:Kaplan-Meier Estimate; D059032:Learning Curve; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000401:mortality / Q000532:radiotherapy*; D058996:Quality Improvement / Q000592:standards / Q000639:trends*; D011787:Quality of Health Care / Q000592:standards / Q000639:trends; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome