Biochemical (prostate-specific antigen) relapse-free survival and toxicity after 125I low-dose-rate prostate brachytherapy.
Khaksar SJ., Laing RW., Henderson A., Sooriakumaran P., Lovell D., Langley SE.
OBJECTIVE: To report our clinical experience and 5-year prostate-specific antigen (PSA) relapse-free survival rate for early-stage prostate cancer after (125)I low-dose-rate prostate brachytherapy. PATIENTS AND METHODS: In all, 300 patients were treated between March 1999 and April 2003, and followed prospectively. Patients were stratified into low-, intermediate- and high-risk groups, and those receiving neoadjuvant androgen deprivation (NAAD) or not. Kaplan-Meier estimates of PSA relapse-free survival and PSA nadirs were obtained for all patients and for the risk groups. Toxicity, as urinary and erectile dysfunction (ED), were reported from a prospective database. RESULTS: The median (range) follow-up was 45 (33-82) months. The actuarial PSA relapse-free survival was 93% at 5 years; 21 (7%) of patients had evidence of biochemical failure as defined by the American Society of Therapeutic Radiation Oncology criteria. There was no significant difference in actuarial survival for patients in the different risk groups, or between those receiving NAAD or not (low-risk 96%, intermediate 89%, high 93%, P = 0.12; NAAD 92%, no NAAD 95%, P = 0.30). Overall the 3-year median PSA level was 0.3 ng/mL (192 men). There was no significant difference in median 3-year PSA levels for different risk groups, or for those treated with or with no NAAD. The 3- and 4-year PSA nadir of <0.5 ng/mL was achieved by 71% and 86% of men, respectively. The acute urinary retention rate was 7%; 5.6% of men developed urethral strictures requiring dilatation, while 2.7% required a transurethral resection of the prostate after implantation, for obstructive symptoms. Of patients with no ED before treatment, 62% had no ED at 2 years, and of these 60% used a phosphodiesterase inhibitor. CONCLUSION: This prospective series confirms the excellent overall biochemical survival after (125)I brachytherapy; the treatment was tolerated well, with early and late urinary toxicity and ED similar to other published results.