Salvage radiotherapy for isolated prostate specific antigen increase after radical prostatectomy: evaluation of prognostic factors and creation of a prognostic scoring system.
OBJECTIVE
This study was performed to evaluate the results and prognostic factors associated with radiotherapy for a detectable serum prostate specific antigen level after radical prostatectomy.


METHODS
From July 1987 through July 2003, 368 patients received radiotherapy for a detectable prostate specific antigen level (biochemical relapse) as the sole evidence of recurrence after radical prostatectomy for node negative prostate cancer. Estimated survival and relapse-free probabilities were obtained via Kaplan-Meier estimation. Associations of patient factors with survival and biochemical relapse were investigated using Cox proportional hazards models.


RESULTS
With a median followup of 5 years the 5 and 8-year freedom from biochemical relapse were an estimated 46% (95% CI 41%-53%) and 35% (95% CI 29%-43%) while survival was 92% (95% CI 89%-95%) and 80% (95% CI 74%-87%), respectively. Patient and treatment variables showing evidence of association with biochemical relapse on multivariate analysis included pathological stage T3a or less vs T3b (seminal vesicle involvement, p = 0.029), pathological Gleason score 7 or less vs 8 or greater (p <0.001) and pre-radiotherapy prostate specific antigen (p <0.001). Four biochemical failure risk groups were created by assigning seminal vesicle involvement, Gleason score and pre-radiotherapy prostate specific antigen each a score of 0 to 2. These individual scores were summed. The freedom from biochemical failure at 5 years for each risk group was 0 to 1-69%, 2-53%, 3-26% and 4 to 5-6%.


CONCLUSIONS
The presence of seminal vesicle involvement and high Gleason score in the radical prostatectomy specimen are inherent predictors of adverse outcome. Early referral for salvage radiotherapy can decrease subsequent biochemical relapse.
Buskirk
Steven J
SJ
Department of Radiation Oncology, Mayo Clinic Jacksonville, 4500 San Pablo Road, Jacksonville, FL 32224, USA. buskirk.steven@mayo.edu
Pisansky
Thomas M
TM
Schild
Steven E
SE
Macdonald
O Kenneth
OK
Wehle
Michael J
MJ
Kozelsky
Timothy F
TF
Collie
A Craig
AC
Ferrigni
Robert G
RG
Myers
Robert P
RP
Prussak
Karin A
KA
Heckman
Michael G
MG
Crook
Julia E
JE
Parker
Alexander S
AS
Igel
Todd C
TC
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000097:blood* / Q000532:radiotherapy*; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000097:blood*; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000097:blood* / Q000532:radiotherapy* / Q000601:surgery; D016879:Salvage Therapy
D017430:Prostate-Specific Antigen