Post prostatectomy multimodality adjuvant therapy for patients at high risk for prostate cancer relapse.

16053 Background: Adjuvant systemic therapy improves survival for many loco-regional cancers, but few data describe adjuvant therapy of prostate cancer. We have conducted a pilot study of multimodality adjuvant therapy (MAT) following radical prostatectomy (RP) in subjects at high risk subjects for disease recurrence. Therapy was modeled after current adjuvant treatment of breast cancer, and included both adjuvant combination chemotherapy and prolonged androgen ablation.,Subjects with high-risk CaP (predicted five year relapse risk >25% by 1999 Kattan post-op nomogram and/or persistent PSA after surgery) were offered MAT. Therapy included 6 cycles of combination chemotherapy Q 3wks (docetaxel [=doc] 70 mg/m, estramustine 280 mg TID × 5 d, or doc 70 mg/m, carboplatin AUC5), followed by 5 yr of androgen deprivation (leuprolide plus bicalutamide). Subjects with pT4 Dz or multiple positive margins were also offered adjuvant radiation therapy following chemotherapy.,Twenty-eight high-risk subjects received MAT. Rx started an average of 78 d after RP. Clinical parameters include: mean age 59.9 yr; Gleason 8-10 64%; pT3b/4 57.1%; N1 70.3%, positive margins 57.1%. Mean predicted relapse risk (Kattan) was 63.6% (2 yr) and 76.4% (5 yr). Ave. chemo cycles = 5.8. Twenty subjects received doc/estramustine, and eight received doc/carboplatin. 7/28 received XRT as part of therapy. Maximum followup is 76.6 mos, ave. followup is 31 mos from RP. There have been no biochemical (PSA) relapses and 26/28 (93%) remain free of disease progression. 2/28 (7%) subjects relapsed clinically, without an elevated PSA at relapse, and both died of cancer. Major chemo toxicities are Gr3-4 neutropenia (65%), edema (30%), DVT (25% with doc/estramustine).,Adjuvant MAT is tolerated by high-risk subjects. Biochemical or clinical failures in subjects treated with MAT are uncommon within this followup period; however, disease relapse in these subjects is aggressive and fatal. Doc/estramustine has an excessive risk of DVT, even with prophylactic coumadin. Doc/carboplatin has little risk of DVT and is our current chemotherapy choice in the adjuvant setting. PSA may be inadequate as the sole method to monitor high risk subjects treated with these adjuvant therapies. No significant financial relationships to disclose.