Table 2.
Univariate and multivariate analyses of predictors associated with acquired T790M mutation (n=59).
| Number of patients | T790M+ (%) | P value | Multivariate analysis | ||
|---|---|---|---|---|---|
| Odds ratio (95% CI) | P value | ||||
| Basic data | |||||
| Sex | 0.584 | ||||
| Male | 20 | 33.9 (%) | |||
| Female | 39 | 66.1 (%) | |||
| Age (years) | 0.466 | ||||
| ≦60 | 30 | 50.8 (%) | |||
| > 60 | 29 | 49.2 (%) | |||
| ECOG PS | 0.219 | ||||
| 0-1 | 50 | 84.7 (%) | |||
| ≥2 | 9 | 15.3 (%) | |||
| Smoking | 0.830 | ||||
| Nonsmoker | 45 | 76.3 (%) | |||
| Current/former | 14 | 23.7 (%) | |||
| EGFR mutation | 0.087 | ||||
| L858R | 23 | 39.0 (%) | |||
| Exon 19 deletion | 35 | 59.3 (%) | |||
| Others | 1 | 1.7 (%) | |||
| Stage | 0.999 | ||||
| IIIB | 3 | 5.1 (%) | |||
| IV | 56 | 94.9(%) | |||
| First-line TKI used | |||||
| Afatinib | 23 | 39.0 (%) | 0.033 | 1 | |
| Erlotinib | 36 | 61.0 (%) | 2.734 (1.144-6.531) | 0.029 | |
| PFS (months) | 0.013 | ||||
| ≦12 | 10 | 16.9 (%) | 1 | ||
| >12 | 49 | 83.1 (%) | 2.958 (1.142-7.661) | 0.025 | |
ECOG PS, Eastern Cooperative Oncology Group performance status; CI, confidence interval; PFS: progression-free survival; EGFR, epidermal growth factor receptor; TKI, tyrosine kinase inhibitor.