Journal of Clinical Oncology, Vol 12, 1868-1875, Copyright © 1994 by American Society of Clinical Oncology
Effects of continued androgen-deprivation therapy and other prognostic factors on response and survival in phase II chemotherapy trials for hormone-refractory prostate cancer: a Southwest Oncology Group report
M Hussain, M Wolf, E Marshall, ED Crawford and M Eisenberger
Veterans Administration Medical Center, Allen Park, MI.
PURPOSE: To assess the impact of prognostic factors, including continued
(orchiectomy) versus discontinued androgen-suppression (nonorchiectomy)
therapy, on chemotherapy response and survival of patients with
hormone-refractory prostate cancer. METHODS: Analysis of five consecutive
Southwest Oncology Group (SWOG) phase II chemotherapy trials was
undertaken. RESULTS: Two hundred five hormone-refractory patients were
evaluated. Eighty-four percent had been orchiectomized. The median survival
durations for the nonorchiectomy and orchiectomy patients were 6 and 7
months, respectively (P = .73). In a univariate analysis, orchiectomy
patients had a significantly longer median time from diagnosis to first
hormone therapy (1.1 v 0.1 years, P = .003), were more likely to have had
chemotherapy initiated > or = 2 years from diagnosis (75% v 56%, P =
.03), had a lower incidence of liver metastases (16% v 30%, P = .05), and
had lower likelihood of being black (8% v 18%, P = .05) when compared with
the nonorchiectomy group. Orchiectomy patients had a marginally significant
longer median time from initial hormone treatment, more prior endocrine
manipulations, lower median baseline alkaline phosphatase levels, and a
lower likelihood of response to chemotherapy when compared with the
nonorchiectomy group. Absence of liver metastases (P = .004), hemoglobin
level > or = 10 g/dL (P < .001), acid phosphatase level > or = 1.2
IU/L (P = .05), response to chemotherapy (P = .001), and > or = 2 years
from initial hormone treatment (P = .01) are important factors for
survival. CONCLUSION: This study failed to show obvious advantages in
response to chemotherapy or survival for patients with continued gonadal
suppression. A prospective randomized trial is suggested to evaluate the
effect of this factor on progression-free and overall survival of patients
with hormone-refractory prostate cancer receiving chemotherapy.