Table 3.

A. Univariate analysis of the association of PIK3CA mutations, KRAS mutations, and PTEN protein expression with clinical outcome of mCRC patients treated with the anti-EGFR monoclonal antibodies cetuximab or panitumumab. Responders are patients who achieved PR; nonresponders are PD and SD (RECIST)
PIK3CAKRASPIK3CA and/or KRASPTEN
WT (%)Mut (%)PWT (%)Mut (%)PWT (%)Mut (%)PNormal (%)Loss (%)P
Objective response
    Responders22 (100)0 (0)0.03820 (90.9)2 (9.1)0.01920 (90.9)2 (9.1)0.00117 (94.4)1 (5.6)0.001
    Nonresponders73 (82.9)15 (17.1)57 (65.5)30 (34.5)44 (50.6)43 (49.4)32 (50.8)31 (42.2)
B. Multivariate logistic regression of the association between PIK3CA mutations, KRAS mutations, and PTEN protein expression and objective response (any single P value is adjusted with respect to other regressors);
OR (95% CI for OR)P
PIK3CA (mutated vs WT)0.1153 (0.000–0.865)0.0337
KRAS (mutated vs WT)0.0660 (0.000–0.452)0.0029
PTEN (loss vs normal)0.0547 (0.001–0.430)0.0012
C. Multivariate Cox survival analysis of the association between KRAS mutations, PIK3CA mutations, and/or PTEN loss and risk of progression
HR (CI95% for HR)P
KRAS (mutated vs WT)1.4974 (0.8909–2.5170)0.128
PIK3CA/PTEN (at least one alterated vs normal)1.8576 (1.1637–2.9653)0.009
  • NOTE: P values measured by Fisher's exact test.

    Abbreviations: OR, odds ratio; 95% CI, 95% confidence interval; HR, hazard ratio.