Loose seeds versus stranded seeds in I-125 prostate brachytherapy: differences in clinical outcome.
OBJECTIVE
To assess clinical outcome in terms of biochemical No evidence of disease (bNED) for patients with stranded seed implants versus loose seed implants in prostate brachytherapy.


METHODS
From December 2000 until October 2006, we treated 896 T< or =2C Nx/0 Mx/0, prostate cancer patients with either stranded seed (n=538) or loose seed (n=358) I-125 implants. A total of 211 patients received a 6 months course of anti-androgen therapy, before treatment, for prostate volume reduction to <50 cc. Patients with very small and large gland volumes or a history of transurethral prostate resection, were preferably treated with stranded seeds, otherwise selection was arbitrary.


RESULTS
The 5-year bNED rates (95% Confidence Interval) for stranded seed patients and loose seed patients were respectively 86% (82-90) and 90% (85-95), the total 5-year bNED rate was 87% (85-90). When adjusted for possible confounding factors in a Cox-regression analysis, type of seed was significantly associated with biochemical failure with a 43% risk reduction (hazard ratio: 0.57; 95% CI: 0.34-0.97) for loose seeds versus stranded seeds.


CONCLUSIONS
These results suggest that seed-type affects clinical outcome in prostate brachytherapy, with better bNED for patients with loose seed implants.
Hinnen
Karel A
KA
Department of Radiation Oncology, University Medical Center Utrecht, Utrecht, the Netherlands. K.A.Hinnen@UMCUtrecht.nl
Moerland
Marinus A
MA
Battermann
Jan J
JJ
van Roermund
Joep G H
JG
Monninkhof
Evelyn M
EM
Jürgenliemk-Schulz
Ina M
IM
van Vulpen
Marco
M
D000230:Adenocarcinoma / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D000368:Aged; D001918:Brachytherapy / Q000379:methods*; D015331:Cohort Studies; D016001:Confidence Intervals; D005500:Follow-Up Studies; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009364:Neoplasm Recurrence, Local / Q000473:pathology*; D009367:Neoplasm Staging; D016016:Proportional Hazards Models; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome
D007457:Iodine Radioisotopes; D017430:Prostate-Specific Antigen