Vinblastine versus vinblastine plus oral estramustine phosphate for patients with hormone-refractory prostate cancer: A Hoosier Oncology Group and Fox Chase Network phase III trial.
OBJECTIVE
To compare vinblastine versus the combination of vinblastine plus estramustine as treatment for patients with hormone-refractory prostate cancer (HRPC).


METHODS
A total of 201 patients with metastatic prostate cancer, progressive after hormonal therapy and antiandrogen withdrawal (if prior antiandrogen treatment), were randomized to receive vinblastine (V) 4 mg/m(2) by intravenous bolus weekly for 6 weeks followed by 2 weeks off, either alone or together with estramustine phosphate (EM-V) 600 mg/m(2) PO days 1 through 42, repeated every 8 weeks. Of 193 eligible patients, 98 received V, and 95 received EM-V.


RESULTS
Overall survival trended in favor of EM-V but was not significantly different as determined by Kaplan-Meier analysis (P =.08). Median survival was 11.9 months for EM-V and 9.2 months for V. EM-V was superior to V for secondary end points of time to progression (P <. 001, stratified log rank test; median 3.7 v 2.2 months, respectively) and for proportion of patients with >/= 50% prostate-specific antigen (PSA) decline sustained for at least 3 monthly measurements (25.2% v 3.2%, respectively; P <.0001). Granulocytopenia was significantly less for EM-V compared with V (grade 2, 3, and 4 = 7%, 7%, and 1% v 27%, 18% and 9%, respectively; P <.0001); however, grade 2 or worse nausea (26% v 7%, respectively; P =.0002) and extremity edema (22% v 8%, respectively; P =.005) were more frequent for EM-V.


CONCLUSIONS
Although overall survival was not significantly greater for the combination, EM-V was superior to V for time to progression and PSA improvement. These results encourage further study of estramustine-based antimicrotubule drug combinations in HRPC.
Hudes
G
G
The Fox Chase Network and Division of Biostatistics, Fox Chase Cancer Center, Philadelphia, PA 19111, USA.
Einhorn
L
L
Ross
E
E
Balsham
A
A
Loehrer
P
P
Ramsey
H
H
Sprandio
J
J
Entmacher
M
M
Dugan
W
W
Ansari
R
R
Monaco
F
F
Hanna
M
M
Roth
B
B
D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D018450:Disease Progression; D004334:Drug Administration Schedule; D004961:Estramustine / Q000008:administration & dosage*; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000188:drug therapy* / Q000473:pathology; D017430:Prostate-Specific Antigen / Q000032:analysis; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000473:pathology; D016019:Survival Analysis; D016896:Treatment Outcome; D014747:Vinblastine / Q000008:administration & dosage*
D000972:Antineoplastic Agents, Phytogenic; D004961:Estramustine; D014747:Vinblastine; D017430:Prostate-Specific Antigen