Table II Univariate and multivariate Cox regression analyses of overall survival since the start of gemcitabine therapy (n = 304)

Factors except sex are regarded as continuous variables. A forward stepwise selection based on Akaike's information criterion was used to select parameters for multivariate analysis. p values of <0.050 are shown in bold. AST, aspartate aminotransferase; ALT, alanine aminotransferase; ALP, alkaline phosphatase.

Univariate analysisMultivariate analysis
Hazard ratioa (95% CI)pHazard ratioa (95% CI)p
Age (years)0.99 (0.98–1.01)0.380
Female sex (vs. male)1.07 (0.83–1.38)0.610
ECOG performance status1.49 (1.22–1.80)<0.0011.36 (1.11–1.67)0.003
Body surface area (m2)0.70 (0.33–1.50)0.360
Leukocytes1.08 (1.05–1.11)<0.00011.04 (1.00–1.08)0.066
Platelets1.07 (0.90–1.28)0.450
Hemoglobin (g/dl)0.93 (0.85–1.01)0.098
Albumin (g/dl)0.61 (0.45–0.82)0.001
Creatinine (mg/dl)1.13 (0.60–2.14)0.700
AST (IU/liter)1.01 (1.00–1.01)<0.001
ALT (IU/liter)1.00 (1.00–1.01)0.033
ALP1.09 (1.06–1.11)<0.00011.07 (1.05–1.10)<0.0001
α1-Antitrypsinb5.92 (3.09–11.37)<0.00013.66 (1.89–7.11)0.0001
α1-Antichymotrypsinb11.60 (2.69–50.01)0.001
Clinical stage IVac (vs. IVb)1.10 (0.85–1.38)0.453
  • a Hazard ratios are per 1,000/mm3 increase for leukocytes, per 10 × 104/mm3 increase for platelets, and per 100 units/liter increase for ALP. Hazard ratios for other continuous variables are per 1 unit increase for each variable.

  • b Logarithmic variable determined by reverse-phase protein microarray.

  • c According to Ref. 23.