Table 3. Incidences of EGFR T790M mutation.
| Groups | T790M positive (n=21) | T790M negative (n=27) | Incidence of EGFR T790M mutation (%) | P value |
|---|---|---|---|---|
| CNS PD | 0.23 | |||
| Yes | 4 | 2 | 66.7 | |
| No | 17 | 25 | 40.4 | |
| Biopsy lesion | 0.87 | |||
| Primary lesion | 5 | 7 | 41.6 | |
| Metastasis lesion | 16 | 20 | 44.4 | |
| EGFR-TKI | 0.24 | |||
| Gefitinib | 14 | 22 | 38.9 | |
| Erlotinib | 7 | 5 | 58.3 | |
| EGFR mutation | 0.14 | |||
| Ex 19 del | 16 | 15 | 51.6 | |
| L858R | 5 | 12 | 29.4 |
CNS, central nervous system; PD, progressive disease; EGFR, epidermal growth factor receptor; TKI, tyrosine kinase inhibitor; Ex, exon; Del, deletion.