Table 2.
Patient characteristics
| Characteristics | No. of Patients |
|---|---|
| N = 51 (100%) | |
| Age, median (range), years | 62 (39–83) |
| Sex | |
| Female | 36 (70.6%) |
| Male | 15 (29.4%) |
| Histologic type | |
| Adenocarcinoma | 50 (98.0%) |
| Squamous cell carcinoma | 1 (2.0%) |
| Tumor stage | |
| IB | 2 (3.9%) |
| IIIA | 3 (5.9%) |
| IIIB | 3 (5.9%) |
| IVA | 21 (41.2%) |
| IVB | 22 (43.1%) |
| M category* | |
| M1a | 13 (25.5%) |
| M1b | 10 (19.6%) |
| M1c | 27 (52.9%) |
| M1a + M1c† | 1 (2.0%) |
| Tissue EGFR genotyping | |
| Exon 19 deletion | 29 (56.9%) |
| L858R | 17 (33.3%) |
| S768I | 2 (3.9%) |
| L861Q | 1 (2.0%) |
| G719S | 1 (2.0%) |
| Exon 19 deletion + L858R‡ | 1 (2.0%) |
| Previous EGFR-TKI therapy | |
| Erlotinib | 10 (19.6%) |
| Afatinib | 13 (25.5%) |
| Gefitinib | 27 (52.9%) |
| > 1 EGFR-TKIs | 1 (2.0%) |
TKI, tyrosine kinase inhibitor
* The information of M category was reclassified at the time of EGFR testing. M category was based on the 8th TMN edition. M1a: lung metastases or pleural/pericardial malignant effusion or nodules; M1b: a single metastatic lesion in a single distant organ; M1c: multiple lesions in a single organ or multiple lesions in multiple organs
†The M category of patient G (Table S7) was M1a at first EGFR testing. M stage was reclassified to M1c at second EGFR testing
‡1 patient had both exon 19 deletion and L858R