Doxorubicin and dose-escalated cyclophosphamide with granulocyte colony-stimulating factor for the treatment of hormone-resistant prostate cancer.
OBJECTIVE
The goals of this study were to define the efficacy and toxicity of doxorubicin and dose-escalated cyclophosphamide (Cy) along with granulocyte colony-stimulating factor (G-CSF) in the treatment of hormone-refractory prostate cancer (HRPC), to determine the maximal-tolerated dose (MTD) of Cy in this regimen, and to evaluate the impact of prior pelvic irradiation (XRT) on MTD and toxicity.


METHODS
Thirty-five patients were treated every 21 days with fixed-dose doxorubicin (40 mg/m2) and Cy 800 to 2,000 mg/m2 (in a cohort dose-escalation schema) along with G-CSF.


RESULTS
Five of 15 patients (33%) with measurable disease obtained an objective response. Sixteen of 35 patients (46%) had a greater than 50% decrease in prostate-specific antigen (PSA) level (95% confidence interval [CI], 28.8% to 63.4%). Ten of 35 patients (28.6%) had a greater than 75% decrease in PSA level. The median survival time was 11 months. The median survival duration of patients with a greater than 50% decrease in PSA level was 23 months, versus a median survival time of 7 months in patients without a PSA response (P = .02). Although 33% of cycles were associated with grade 4 neutropenia, febrile neutropenia occurred in only 7.8% of all cycles. Thrombocytopenia and anemia were rare. Nonhematologic toxicity was minimal. Patients who had received prior pelvic XRT had a lower Cy MTD, but their hematologic toxicity was not appreciably different.


CONCLUSIONS
This is a well-tolerated, active regimen for the treatment of HRPC. Toxicity was not different in patients with prior pelvic XRT, although these patients had a lower MTD.
Small
E J
EJ
Department of Medicine, Mt Zion Cancer Center, San Francisco, CA 94115, USA.
Srinivas
S
S
Egan
B
B
McMillan
A
A
Rearden
T P
TP
D000230:Adenocarcinoma / Q000188:drug therapy* / Q000401:mortality; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects* / Q000627:therapeutic use*; D015331:Cohort Studies; D003520:Cyclophosphamide / Q000008:administration & dosage / Q000009:adverse effects; D004305:Dose-Response Relationship, Drug; D004317:Doxorubicin / Q000008:administration & dosage / Q000009:adverse effects; D016179:Granulocyte Colony-Stimulating Factor / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000401:mortality; D016019:Survival Analysis
D016179:Granulocyte Colony-Stimulating Factor; D004317:Doxorubicin; D003520:Cyclophosphamide; D017430:Prostate-Specific Antigen