EVALUATION OF ADJUVANT ESTRAMUSTINE PHOSPHATE, CYCLOPHOSPHAMIDE, AND OBSERVATION ONLY FOR NODE-POSITIVE PATIENTS FOLLOWING RADICAL PROSTATECTOMY AND DEFINITIVE IRRADIATION

In 1978 the National Prostate Cancer Project launched two protocols ev aluating adjuvant therapy following surgery (Protocol 900) or irradiat ion (Protocol 1,000) for clinically localized prostate cancer. All pat ients underwent staging pelvic lymphadenectomy. Following definitive t reatment, patients were randomized to either cyclophosphamide 1 gram/m (2)-IV every 3 weeks for 2 years, estramustine phosphate 600 mg/m(2)-p o daily for up to 2 years, or to observation only. Patient accession c losed in 1985 and includes 184 to Protocol 900 (170 evaluable) and 253 to Protocol 1,000 (233 evaluable). Lymph node involvement was identif ied in 198 patients (49% of total), 29% in Protocol 900, 63% in Protoc ol 1,000. Median progression-free survival (PFS) for patients with nod al involvement in Protocol 1,000 receiving estramustine phosphate adju vant was longer (37.3 mo) compared to cyclophosphamide (30.9 mo) and t o no treatment (20.9 mo). Median PFS for patients with limited nodal d isease in Protocol 1,000 was longer (39.9 mo), regardless of adjuvant, compared to extensive nodal disease (20.7 mo). However for patients w ith extensive nodal involvement, those receiving adjuvant estramustine phosphate experienced a significantly longer median PFS (32.8 mo) com pared to adjuvant cyclophosphamide (22.7 mo) and no adjuvant (12.9 mo) . We conclude that adjuvant estramustine phosphate is of benefit in pr ostate cancer patients with extensive pelvic node involvement receivin g irradiation as definitive treatment. (C) 1996 Wiley-Liss, Inc.