Prognostic Significance of Prostate-specific Antigen Level Two Months after Maximal Androgen Blockade in Metastatic Prostate Cancer

Park, Bum Jin; Lee, Young Goo; Ahn, Hye Kyung

Abstract

PURPOSE: The aim of this study was to analyze the prognostic significance of pre- and post-treatment serum prostate-specific antigen (PSA) level, together with a variety of other clinicopathological parameters, in patients with metastatic prostate cancer receiving maximal androgen blockade (MAB).
MATERIALS AND METHODS
The PSA levels before and during MAB, together with various clinicopathological parameters, were measured in 65 patients with newly diagnosed metastatic prostate cancer. The prognostic significance of these parameters, including the PSA level two and six months after MAB (PSA2MO and PSA6MO), a 50% reduction in the pretreatment PSA level after MAB (PSA50), the extent of disease (EOD), performance state, Gleason score and pretreatment hemoglobin, were analyzed by both univariate and multivariate tests.
RESULTS
Of the forty-nine patients with a pretreatment PSA level of > or =50ng/ml, twenty-four (24/49, 48.9%) showed normalized (< or =4ng/ml) PSA2MO, and three of these (3/24, 12.5%) died of metastatic prostate cancer. Twenty-five patients (25/49, 51.1%) showed no normalization of the PSA2MO, and sixteen of these (16/25, 64%) died of metastatic prostate cancer. Of the patients with a pretreatment PSA level > or =50ng/ml, patients with a normalized PSA2MO showed a higher survival rate than those with a non-normalized PSA2MO from the univariate analysis using the Log-Rank test (p=0.0001), and PSA2MO was revealed as the most useful prognostic factor (p=0.022) from the multivariate analysis using the Cox proportional hazards regression model.
CONCLUSIONS
A normalized (< or =4ng/ml) PSA level 2 months after MAB (PSA2MO) in metastatic prostate carcinoma was found to be the most useful prognostic factor in metastatic prostate cancer patients with a pretreatment PSA level of > or =50ng/ml.