title: The learning curve in prostate seed implantation.
abstract: OBJECTIVE
  To describe the learning curve in prostate seed implantation, according to the experience with two groups of 100 patients.
  
  
  METHODS
  A perineal, ultrasound-guided implantation technique with manual afterloading was used in all patients. Of a total of 255 patients treated over the period 1989 through 1998, the results of the first hundred patients were compared in relation to the last hundred patients. In the first group single seeds were used, while in the second group RAPID Strands were applied.
  
  
  RESULTS
  Although there is a difference in the follow-up period, a significant difference is found in disease-free survival between the two groups. PSA progression was noticed in 39% of patients in the first group and in 12% in the other group. The strongest prognostic factor, however, is the initial PSA value. Toxicity is relatively low, though higher in the second group.
  
  
  CONCLUSIONS
  The results obtained in the second hundred patients are in agreement with data from literature. Differences in outcome between the two groups are, however, not only explained by differences in technique, but also by selection and total number of implanted seeds.
authors.affiliation: University Medical Center Utrecht, Department of Radiation-Oncology, Utretcht, The Netherlands.
authors.forename: J J
authors.initials: JJ
authors.lastname: Battermann
authors.forename: C A
authors.initials: CA
authors.lastname: van Es
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy / Q000379:methods*; D002983:Clinical Competence; D018572:Disease-Free Survival; D005500:Follow-Up Studies; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D011214:Practice, Psychological; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000473:pathology / Q000532:radiotherapy*; D018084:Ultrasonography, Interventional
chemical_list: D007457:Iodine Radioisotopes; D017430:Prostate-Specific Antigen