Efficacy of salvage radiotherapy plus 2-year androgen suppression for postradical prostatectomy patients with PSA relapse.
OBJECTIVE
To determine the efficacy of a combined approach of radiotherapy (RT) plus 2-year androgen suppression (AS) as salvage treatment for prostate-specific antigen (PSA) relapse after radical prostatectomy (RP).


METHODS
Seventy-five patients with PSA relapse after RP were treated with salvage RT plus 2-year AS, as per a pilot, prospective study. AS started within 1 month after completion of salvage RT and consisted of nilutamide for 4 weeks and buserelin acetate depot subcutaneously every 2 months for 2 years. Relapse-free rate including freedom from PSA relapse was estimated using the Kaplan-Meier method. PSA relapse was defined as a PSA rise above 0.2 ng/mL with two consecutive increases over a minimum of 3 months. A Cox regression analysis was performed to evaluate prognostic factors for relapse.


RESULTS
Median age of the cohort was 63 years at the time of salvage RT. Median follow-up from salvage RT was 6.4 years. All achieved initially complete PSA response (< 0.2) with the protocol treatment. Relapse-free rate including the freedom from PSA relapse was 91.5% at 5 years and 78.6% at 7 years. Overall survival rate was 93.2% at both 5 and 7 years. On Cox regression analysis, pT3 stage and PSA relapse less than 2 years after RP were significant prognostic factors for relapse.


CONCLUSIONS
The combined treatment of salvage RT plus 2-year AS yielded an encouraging result for patients with PSA relapse after RP and needs a confirmatory study.
Choo
Richard
R
Mayo Clinic, Department of Radiation Oncology, Rochester, MN 55905, USA. choo.c@mayo.edu
Danjoux
Cyril
C
Gardner
Sandra
S
Morton
Gerard
G
Szumacher
Ewa
E
Loblaw
D Andrew
DA
Cheung
Patrick
P
Pearse
Maria
M
D000368:Aged; D000726:Androgen Antagonists / Q000627:therapeutic use; D002064:Buserelin / Q000627:therapeutic use; D004334:Drug Administration Schedule; D005500:Follow-Up Studies; D006801:Humans; D048289:Imidazolidines; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000097:blood / Q000188:drug therapy* / Q000532:radiotherapy*; D010865:Pilot Projects; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000097:blood*; D011468:Prostatectomy / Q000379:methods; D011471:Prostatic Neoplasms / Q000097:blood / Q000188:drug therapy* / Q000532:radiotherapy* / Q000601:surgery; D012044:Regression Analysis; D016879:Salvage Therapy / Q000379:methods*; D015996:Survival Rate; D013997:Time Factors
D000726:Androgen Antagonists; D048289:Imidazolidines; C021277:nilutamide; D017430:Prostate-Specific Antigen; D002064:Buserelin