Table 2. EGFR mutation frequency and subtype for the tissue/cytology and plasma evaluable populations.
| Characteristic | EGFR mutation frequency, n/N (%)a | |
|---|---|---|
| Tissue/cytology samples | Plasma samples | |
| Overall | 13/126 (10.3) | 10/145 (6.9) |
| Histological subtype | ||
| Adenocarcinoma | 12/103 (11.7) | 9/115 (7.8) |
| Non-adenocarcinoma | 1/20 (5.0) | 1/26 (3.8) |
| TNM stage | ||
| IIIA | 0/8 (0.0) | 0/12 (0.0) |
| IIIB | 0/8 (0.0) | 0/9 (0.0) |
| IV | 13/110 (11.8) | 10/124 (8.1) |
| TNM stage IV | ||
| M1a | 2/21 (9.5)b | 1/23 (4.3) |
| M1b | 9/67 (13.4)b | 9/78 (11.5) |
| EGFR mutation subtype | ||
| Exon 19 deletions | 7/13 (53.8) | 5/10 (50.0) |
| L858R | 4/13 (30.8) | 5c/10 (50.0) |
| L861Q | 1/13 (7.7) | 0/10 (0.0) |
| G719X+S768I | 1/13 (7.7) | 0/10 (0.0) |
EGFR, epidermal growth factor receptor; TNM, tumor, node, metastasis. a, n/N, number of EGFR mutation positive samples/total number of samples tested; b, data for M1 staging of two samples is not known; c, one L858R mutation was found in the plasma of a patient who was initially tested EGFR wild type in the tissue sample.