The impact of race on biochemical disease-free survival in early-stage prostate cancer patients treated with surgery or radiation therapy.

Abstract

To assess the impact of race on biochemical freedom from recurrence in patients with early-stage prostate cancer treated either by radical prostatectomy or radiation therapy. Between July 1989 and December 1994, 693 patients with early-stage prostate cancer were treated with radiation (302 patients) or by radical prostatectomy (391 patients) at Barbara Ann Karmanos Cancer Institute/Wayne State University. Stage, Gleason score, race, pretreatment PSA, and follow-up PSA values were abstracted. There were 387 Caucasian males (CM) and 306 African-American males (AAM). None of the patients received hormone therapy. Radiation therapy was delivered using photon irradiation (249 patients, median dose 69 Gy) or mixed neutron/photon irradiation (53 patients, median dose 10 NGy + 38 PGy). Median follow-up was 36 months (range 2-70) for CM and 35 months (range 1-70) for AAM. Thirty-seven percent of patients treated surgically were AAM, compared to 53% in the radiation group (p = 0001). AAM had a higher median prostate-specific antigen (PSA) than CM (9.78 ng/ml vs. 8.0 ng/ml, p = 0.01). Thirty-three percent of AAM had a pretreatment PSA greater than 15 ng/ml compared to 20% of CM (p = 0.00001). Disease-free survival (DFS) by race was equivalent at 36 months, 81% for CM and 77% for AAM (p = NS). For patients with PSA < or =15, DFS rates were 87% and 85% for CM and AAM, respectively. DFS rates for patients with PSA >15 were 61% for CM and 64% for AAM (p = NS). Significant prognostic factors on multivariate analysis included pretreatment PSA (p = 0.0001) and Gleason score (p = 0.0001). Race does not appear to adversely affect biochemical disease-free survival in males treated for early-stage prostate cancer. African-American males with early-stage prostate cancer should expect similar biochemical disease-free survival rates to those seen in Caucasian males.