Table 4.
Multivariate Analysis of Predictors of Acquiring T790M Mutation
| Characteristics | All Patients (n = 87) | Patients with T790M (n = 55) | Multivariate Analysis, OR (95% CI), p value |
|---|---|---|---|
| EGFR mutation subtypes, No. (%) | |||
| Exon 19 deletion | 54 | 38 (70.4) | 2.3 (0.84–6.25), 0.104 |
| Exon 21 L858R point mutation# | 33 | 17 (51.5) | |
| First-line EGFR-TKI, No. (%) | |||
| Gefitinib | 57 | 40 (70.2) | 1.6 (0.41–6.38), 0.491 |
| Erlotinib | 14 | 6 (42.9) | 0.5 (0.09–2.70), 0.424 |
| Afatinib# | 16 | 9 (56.3) | |
| Best tumour response, No (%) | 4.1 (1.24–13.50), 0.021 | ||
| Partial response | 72 | 49 (68.1) | |
| Stable disease# | 15 | 6 (40.0) | |
| New lung metastases, No. (%) | |||
| Yes | 42 | 31 (73.8) | 1.6 (0.54–4.55), 0.404 |
| No# | 45 | 24 (53.3) | |
| New symptomatic brain metastases, No. (%) | 0.2 (0.04–0.88), 0.034 | ||
| Yes | 10 | 3 (30.0) | |
| No# | 77 | 52 (67.5) | |
| New intrathoracic lymph nodes metastases, No. (%) | 0.3 (0.11–0.94), 0.038 | ||
| Yes | 21 | 10 (47.6) | |
| No# | 66 | 45 (68.2) |
Notes: Bold p values are statistically significant. #Parameters as the reference group.
Abbreviations: EGFR, epidermal growth factor receptor; TKI, tyrosine kinase inhibitor; OR, odds ratio; 95% CI, 95% confidence interval.