Nonrandomized comparison of surgery with and without adjuvant pelvic irradiation for patients with pT3N0 adenocarcinoma of the prostate.
The purpose of this study was to evaluate the outcome of radical prostatectomy alone and compare it with that of surgery followed by planned adjuvant radiotherapy in patients with pT3N0 prostate cancer (CaP). A total of 402 patients with CaP were treated with prostatectomy, including 311 (77%) who received a planned course of adjuvant radiotherapy (RT) (surgery [S] + RT) to the prostatic fossa (median dose: 48 Gy) and 91 (23%) who had surgery alone. Patients in the former group had worse risk factors than those in the latter group, such as a higher clinical and pathologic stage (p = 0.001), higher Gleason score (p = 0.09), and higher preoperative prostate-specific antigen (PSA) level (p = 0.0001). PSA failure was defined as more than 0.05 ng/ml. Median follow-up was 59 months. The 5- and 10-year overall survival for the 311 S+RT patients was 91% and 81%, respectively, and it was similar for those 91 in the surgery-alone group, p = 0.59. The 5- and 10-year probability of freedom from PSA and/or clinical failure for the former group was 70% and 53%, respectively, whereas it was 66% and 46%, respectively, for the latter group, p = 0.72. Any recurrence developed in a total of 96 (31%) patients in the S+RT group as compared with 23 (25%) in the surgery-alone group. Local recurrence was noted in 10 (3.2%) S+RT and in 6 (6.6%) surgery-alone patients (N.S.). The time to clinical or chemical recurrence was also similar for both treatment groups (median time: 3.0 versus 3.8 years). Patients with pT3b tumors had relatively poor 5- and 10-year disease-free survival (53% and 32%, respectively, for S+RT and 38% and 0%, respectively, for surgery alone, p = 0.82). In multivariate analyses, pathologic stage and Gleason score were independent predictors of recurrence, each with p < 0.001 after controlling for the other. The worst prognostic category included patients with pT3bN0, Gleason score 7-10 disease who had 5.0 times the risk of recurrence as compared with pT3aN0, Gleason score 2-6 patients. No significant difference in disease-free survival by the treatment group was seen in Cox regression analysis controlling for pathologic stage (p = 0.59), Gleason score (p = 0.99), and PSA (p = 0.28). S+RT patients were predicted to have disease recurrence at 83% the rate of surgery-alone patients, p = 0.42. Preoperative PSA (>25 ng/ml) was predictive of recurrence (2.0 x risk) in univariate analysis, but it was not a significant predictor in multivariate analysis. It appears that moderate-dose, localized fields postoperative irradiation reduced the incidence of local recurrence in patients who were at a higher risk of recurrence as compared with those treated with surgery alone. New treatment strategies need to be developed to manage pT3bN0, Gleason score 7-10 patients whose 10-year disease-free survival was poor.
Petrovich
Z
Z
Department of Radiation Oncology, University of Southern California School of Medicine, Los Angeles, California, USA.
Lieskovsky
G
G
Langholz
B
B
Huberman
M
M
Streeter
O
O
Skinner
D G
DG
D000230:Adenocarcinoma / Q000532:radiotherapy* / Q000556:secondary / Q000601:surgery*; D000368:Aged; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D016016:Proportional Hazards Models; D017430:Prostate-Specific Antigen / Q000097:blood; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery*; D018714:Radiotherapy, Adjuvant; D016019:Survival Analysis
D017430:Prostate-Specific Antigen