Table 2.

Multivariate Cox regression OS analysis

A. Prognostic factors prior to the initiation of therapy in androgen-independent prostate cancer patients
VariableCategories
OS risk from baseline
PositiveNegativeHR (95% CI)P*
Baseline CTC number>5<51.81 (1.10-2.97)0.019
ECOG status at study entry2 vs 1 vs 01.48 (1.05-2.08)0.025
Baseline hemoglobin (g/dL)Continuous0.83 (0.71-0.96)0.013
Baseline LDH (IU/mL)Continuous1.00 (1.00-1.00)<0.001
Baseline alkaline phosphatase (IU/mL)Continuous1.00 (1.00-1.00)0.449
Line of therapyContinuous (1-6)1.09 (0.87-1.36)0.439
Type of therapy (taxotere: yes/no)YesNo0.72 (0.45-1.17)0.185
Bone metastasis?YesNo1.60 (0.56-4.54)0.376
B. Prognostic factors 9-12 weeks after initiation of therapy in androgen-independent prostate cancer patients
9-12 wk CTC number>5<54.40 (2.43-7.97)<0.001
ECOG status at study entry2 vs 1 vs 02.50 (1.70-3.67)<0.001
Line of therapyContinuous (1-6)1.16 (0.89-1.53)0.277
Type of therapy (taxotere: yes/no)YesNo1.22 (0.67-2.25)0.515
9-12 wk PSA reduction from baseline (%)<30%>30%1.38 (0.77-2.47)0.281
  • NOTE: See supplementary table for univariate analysis.

  • * P value from Wald test of Z statistic.

  • Determined from serum drawn on the same date as the blood drawn for CTC.