TY - JOUR
T1 - Higher prostate-specific antigen levels predict improved survival in patients with hormone-refractory prostate cancer who have skeletal metastases and normal serum alkaline phosphatase
AU - Xie, Wanling
AU - Nakabayashi, Mari
AU - Regan, Meredith M.
AU - Oh, William K.
PY - 2007/12/15
Y1 - 2007/12/15
N2 - BACKGROUND. Higher prostate-specific antigen (PSA) and alkaline phosphatase (ALK-P) levels predicted worse survival in men with metastatic hormone-refractory prostate cancer (HRPC). In the current study, the authors evaluated the combined effects of PSA and ALK-P on survival. METHODS. Two hundred twenty-four men who had HRPC with bone metastases and who were receiving chemotherapy were identified, and 143 of those men had data available on both ALK-P and PSA levels at chemotherapy initiation. The primary endpoint of the study was overall survival (OS) after chemotherapy. The men were dichotomized into normal and abnormal ALK-P groups according to levels based on institutional normal ranges. The effect of PSA was evaluated as both a categorical value and a continuous value using Cox regression. RESULTS. Eighty-nine of 143 patients (62%) had elevated ALK-P levels. The median PSA was 147 ng/mL (93 ng/mL in patients with normal ALK-R 171 ng/mL in patients with elevated ALK-P). At a median follow-up of 30 months after chemotherapy initiation, 93 patients had died. The median OS after chemotherapy was 15.8 months (95% confidence interval, 12.8-18.4 months) and was significantly longer if ALK-P was in the normal range (21.3 months vs 14 months; P = .005). For the group with normal ALK-P levels, the median OS was 12.5 months, 24.5 months, and 36.9 months for patients with low, medium, and high PSA levels, respectively. In contrast, the effect of PSA on survival was not as evident in the group with elevated ALK-P levels (16.5 months vs 11.9 months vs 12.1 months, respectively; P =.14 for interaction). Age-adjusted multivariate analysis demonstrated statistically significant interactions of PSA and ALK-P with OS (P = .02). CONCLUSIONS. ALK-P significantly predicted OS in men with HRPC who had bone metastases. In patients with normal ALK-P levels, higher PSA levels were associated with improved survival.
AB - BACKGROUND. Higher prostate-specific antigen (PSA) and alkaline phosphatase (ALK-P) levels predicted worse survival in men with metastatic hormone-refractory prostate cancer (HRPC). In the current study, the authors evaluated the combined effects of PSA and ALK-P on survival. METHODS. Two hundred twenty-four men who had HRPC with bone metastases and who were receiving chemotherapy were identified, and 143 of those men had data available on both ALK-P and PSA levels at chemotherapy initiation. The primary endpoint of the study was overall survival (OS) after chemotherapy. The men were dichotomized into normal and abnormal ALK-P groups according to levels based on institutional normal ranges. The effect of PSA was evaluated as both a categorical value and a continuous value using Cox regression. RESULTS. Eighty-nine of 143 patients (62%) had elevated ALK-P levels. The median PSA was 147 ng/mL (93 ng/mL in patients with normal ALK-R 171 ng/mL in patients with elevated ALK-P). At a median follow-up of 30 months after chemotherapy initiation, 93 patients had died. The median OS after chemotherapy was 15.8 months (95% confidence interval, 12.8-18.4 months) and was significantly longer if ALK-P was in the normal range (21.3 months vs 14 months; P = .005). For the group with normal ALK-P levels, the median OS was 12.5 months, 24.5 months, and 36.9 months for patients with low, medium, and high PSA levels, respectively. In contrast, the effect of PSA on survival was not as evident in the group with elevated ALK-P levels (16.5 months vs 11.9 months vs 12.1 months, respectively; P =.14 for interaction). Age-adjusted multivariate analysis demonstrated statistically significant interactions of PSA and ALK-P with OS (P = .02). CONCLUSIONS. ALK-P significantly predicted OS in men with HRPC who had bone metastases. In patients with normal ALK-P levels, higher PSA levels were associated with improved survival.
KW - Alkaline phosphatase
KW - Bone metastases
KW - Hormone-refractory prostate cancer
KW - Prostate-specific antigen
KW - Survival
UR - https://www.scopus.com/pages/publications/37049020294
U2 - 10.1002/cncr.23111
DO - 10.1002/cncr.23111
M3 - Article
C2 - 17960608
AN - SCOPUS:37049020294
SN - 0008-543X
VL - 110
SP - 2709
EP - 2715
JO - Cancer
JF - Cancer
IS - 12
ER -