title: Patterns of failure after iodine-125 seed implantation for prostate cancer.
abstract: OBJECTIVE
  To determine the site of relapse when biochemical failure (BF) occurs after iodine-125 seed implantation for prostate cancer.
  
  
  METHODS
  From 2001-2009, 500 men underwent implantation in Wellington, New Zealand. Men who sustained BF were placed on relapse guidelines that delayed restaging and intervention until the prostate-specific antigen (PSA) was ⩾20 ng/mL.
  
  
  RESULTS
  Most implants (86%) had a prostate D90 of ⩾90%, and multivariate analysis showed that this parameter was not a variable that affected the risk of BF. Of 21 BFs that occurred, the site of failure was discovered to be local in one case and distant in nine cases. Restaging failed to identify the site of relapse in two cases. In nine cases the trigger for restaging had not been reached.
  
  
  CONCLUSIONS
  If post-implant dosimetry is generally within the optimal range, distant rather than local failure appears to be the main cause of BF. Hormone treatment is therefore the most commonly indicated secondary treatment intervention (STI). Delaying the start of STI prevents the unnecessary treatment of men who undergo PSA 'bounce' and have PSA dynamics initially mimicking those of BF.
authors.affiliation: Prostate Cancer Trials Unit, Department of Pathology and Molecular Medicine, University of Otago, Wellington, New Zealand; Radiation Oncology, Southern Cross Hospital, Wellington, New Zealand. Electronic address: David.Lamb@otago.ac.nz.
authors.forename: David S
authors.initials: DS
authors.lastname: Lamb
authors.affiliation: Medical Physics, Southern Cross Hospital, Wellington, New Zealand.
authors.forename: Lynne
authors.initials: L
authors.lastname: Greig
authors.affiliation: Urology, Southern Cross Hospital, Wellington, New Zealand.
authors.forename: Grant L
authors.initials: GL
authors.lastname: Russell
authors.affiliation: Prostate Cancer Trials Unit, Department of Pathology and Molecular Medicine, University of Otago, Wellington, New Zealand; Urology, Southern Cross Hospital, Wellington, New Zealand.
authors.forename: John N
authors.initials: JN
authors.lastname: Nacey
authors.affiliation: Omahu Urology Clinic, Hawkes Bay, New Zealand.
authors.forename: Kim
authors.initials: K
authors.lastname: Broome
authors.affiliation: Urology, Southern Cross Hospital, Wellington, New Zealand.
authors.forename: Rod
authors.initials: R
authors.lastname: Studd
authors.affiliation: Prostate Cancer Trials Unit, Department of Pathology and Molecular Medicine, University of Otago, Wellington, New Zealand.
authors.forename: Brett
authors.initials: B
authors.lastname: Delahunt
authors.affiliation: Radiation Oncology, Southern Cross Hospital, Wellington, New Zealand.
authors.forename: Douglas
authors.initials: D
authors.lastname: Iupati
authors.affiliation: Anesthetics, Southern Cross Hospital, Wellington, New Zealand.
authors.forename: Mohua
authors.initials: M
authors.lastname: Jain
authors.affiliation: Medical Physics, Southern Cross Hospital, Wellington, New Zealand.
authors.forename: Colin
authors.initials: C
authors.lastname: Rooney
authors.affiliation: Prostate Cancer Trials Unit, Department of Pathology and Molecular Medicine, University of Otago, Wellington, New Zealand.
authors.forename: Judy
authors.initials: J
authors.lastname: Murray
authors.affiliation: Prostate Cancer Trials Unit, Department of Pathology and Molecular Medicine, University of Otago, Wellington, New Zealand.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Lamb
authors.affiliation: Prostate Cancer Trials Unit, Department of Pathology and Molecular Medicine, University of Otago, Wellington, New Zealand.
authors.forename: Peter B
authors.initials: PB
authors.lastname: Bethwaite
mesh_terms: D000328:Adult; D000368:Aged; D001918:Brachytherapy / Q000379:methods*; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009364:Neoplasm Recurrence, Local / Q000097:blood* / Q000532:radiotherapy; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood / Q000532:radiotherapy*; D012189:Retrospective Studies; D017211:Treatment Failure
chemical_list: D007457:Iodine Radioisotopes; D017430:Prostate-Specific Antigen
keywords: Low-dose-rate; Patterns of failure; Post-implant dosimetry; Prostate brachytherapy