Long-term follow-up of a prospective trial of trimodality therapy of weekly paclitaxel, radiation, and androgen deprivation in high-risk prostate cancer with or without prior prostatectomy.

Abstract

Weekly paclitaxel, concurrent radiation, and androgen deprivation (ADT) were evaluated in patients with high-risk prostate cancer (PC) with or without prior prostatectomy (RP). Eligible post-RP patients included: pathological T3 disease, or rising prostate-specific antigen (PSA) ≥ 0.5 ng/mL post-RP. Eligible locally advanced PC (LAPC) patients included: 1) cT2b-4N0N+, M0; 2) Gleason score (GS) 8-10; 3) GS 7 + PSA 10-20 ng/mL; or 4) PSA 20-150 ng/mL. Treatment included ADT (4 or 24 months), weekly paclitaxel (40, 50, or 60 mg/m(2)/wk), and pelvic radiation therapy (total dose: RP = 64.8 Gy; LAPC = 70.2 Gy). Fifty-nine patients were enrolled (LAPC, n = 29; RP, n = 30; ADT 4 months, n = 29; 24 months, n = 30; whites n = 29, African Americans [AA], n = 28). Baseline characteristics (median [range]) were: age 67 (45-86 years), PSA 5.9 (0.1-92.1 ng/mL), GS 8 (6-9). At escalating doses of paclitaxel, 99%, 98%, and 95% of doses were given with radiation and ADT, respectively, with dose modifications required primarily in RP patients. No acute Grade 4 toxicities occurred. Grade 3 toxicities were diarrhea 15%, urinary urgency/incontinence 10%, tenesmus 5%, and leukopenia 3%. Median follow-up was 75.3 months (95% CI: 66.8-82.3). Biochemical progression occurred in 24 (41%) patients and clinical progression in 11 (19%) patients. The 5- and 7-year OS rates were 83% and 67%. There were no differences in OS between RP and LAPC, 4- and 24-month ADT, white and AA patient categories. In addition to LAPC, to our knowledge, this is the first study to evaluate concurrent chemoradiation with ADT in high-risk RP patients. With a median follow-up of 75.3 months, this trial also represents the longest follow-up of patients treated with taxane-based chemotherapy with EBRT in high-risk prostate cancer. Concurrent ADT, radiation, and weekly paclitaxel at 40 mg/m(2)/week in RP patients and 60 mg/m(2)/week in LAPC patients is feasible and well-tolerated.