Long-term outcome of patients with prostate cancer and pathologic seminal vesicle invasion (pT3b): effect of adjuvant radiotherapy.

OBJECTIVES: To evaluate the long-term outcome of patients with prostate cancer who have pathologic seminal vesicle invasion without lymph node metastasis (pT3bN0M0) and compare management strategies.

METHODS: From October 1987 to August of 1997, 43 men underwent radical prostatectomy at Thomas Jefferson University Hospital, had pT3bN0M0 disease, complete preoperative and postoperative prostate-specific antigen (PSA) data, and a minimum of 2 years of follow-up. Eighteen patients with undetectable postoperative PSA levels received adjuvant radiotherapy (RT) within 6 months of surgery. Twelve patients with undetectable PSA levels postoperatively were considered for salvage treatment at biochemical progression. Thirteen patients with persistently elevated PSA levels postoperatively underwent immediate salvage RT. We evaluated the prognostic factors for freedom from biochemical failure (bNED), distant metastasis (DM), disease-specific survival, and overall survival.

RESULTS: The median follow-up time was 5.9 years (range 2 to 10). Patients who received adjuvant RT had significantly greater 5-year bNED survival than patients who did not (80% versus 8%, P <0.001) and increased freedom from DM that was of borderline significance (P = 0.05). The 5-year survival estimates for DM were 0% for the adjuvant RT versus 17% for the observed patient group. In patients with undetectable postoperative PSA levels, the preoperative PSA level was an independent prognostic factor for later disease progression. Patients with a preoperative PSA level of less than 20 ng/mL showed significantly greater 5-year bNED survival than those with a preoperative PSA level of 20 ng/mL or greater (56% versus 32%, P <0.05). The survival curves for risk of DM and death from prostate cancer for those two patient groups were not significantly different statistically.

CONCLUSIONS: Although pathologic seminal vesicle invasion has been associated with poor prognosis and high DM risk, adjuvant RT may result in improved bNED survival in patients with undetectable PSA levels after radical prostatectomy. The effect on clinical outcome awaits additional follow-up.