Conformal radiotherapy for detectable PSA following radical prostatectomy: efficacy and predictive factors of recurrence.
BACKGROUND
Many studies have analyzed outcomes following salvage radiation therapy (RT) after biochemical recurrence--defined as the presence of detectable serum prostate-specific antigen (PSA)--following radical prostatectomy (RP). However, the management of patients with detectable PSA following RP, which is not specific for tumor recurrence, is a matter of debate. This study aimed to evaluate oncological results of three-dimensional conformal RT (3D-CRT) in patients who had biochemical recurrence.


METHODS
The study included patients who underwent RP, who had a postoperative PSA level--determined between 2 and 4 months after surgery--that was greater than 0.1 ng/ml, and who subsequently received monotherapy with 3D-CRT on the prostate bed. The patients' clinical, characteristics and the pathological characteristics of their biopsy specimens were recorded. The main endpoint was biochemical failure after 3D-CRT, defined as three consecutive elevated PSA levels.


RESULTS
The tumors in the 46 patients included 4 (9%) pT2a, 7 (15%) pT2b, 14 (30%) pT2c, 10 (22%) pT3a, 10 (22%) pT3b, and 1 (2%) pT4 tumor. The Gleason score was 7 or higher in 37 patients (80%). Positive surgical margins were seen in 37 patients (80%). The patients had a median postoperative PSA level of 0.29 ng/ml (range, 0.1-5.8 ng/ml) and a median PSA doubling time (PSADT) before RT of 6 months (range, 1-53 months). The rate of biochemical recurrence free survival after 3D-RT was 66% at 30 months. Preoperative PSA, PSADT before RT, and D'Amico scores were significantly associated with biochemical failure after 3D-CRT (p < 0.05).


CONCLUSIONS
In cases of persistent PSA following RP for prostate cancer, 3D-CRT can be used as monotherapy with a significant chance of recurrence free survival. Preoperative PSA, PSADT before RT, and D'Amico score are predictive factors of recurrence following RT.
Delongchamps
Nicolas B
NB
Department of Urology, Cochin Hospital, Descartes University, Paris, France.
Zerbib
Marc
M
Mejean
Arnaud
A
Rouach
Yannick
Y
Debre
Bernard
B
Peyromaure
Michael
M
D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood; D001706:Biopsy; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000097:blood / Q000175:diagnosis / Q000517:prevention & control*; D011182:Postoperative Care / Q000379:methods*; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000097:blood*; D011468:Prostatectomy / Q000379:methods*; D011471:Prostatic Neoplasms / Q000097:blood / Q000532:radiotherapy* / Q000601:surgery; D020266:Radiotherapy, Conformal / Q000379:methods*; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed
D014408:Biomarkers, Tumor; D017430:Prostate-Specific Antigen