Table 1. Characteristics of the study population.
| Characteristics | Subgroups | N (%) |
|---|---|---|
| Age | <65 years | 35 (79.5) |
| ≥65 years | 9 (20.5) | |
| Sex | Male | 25 (56.8) |
| Female | 19 (43.2) | |
| Smoking | Never | 17 (38.6) |
| Ever | 27 (61.4) | |
| ECOG PS | 0 or 1 | 36 (81.8) |
| 2 | 8 (18.2) | |
| Histology | Adenocarcinoma | 41 (93.2) |
| Non-adenocarcinoma | 3 (6.8) | |
| EGFR mutation | Exon 19 deletion | 25 (56.8) |
| Exon 21 L858R | 18 (40.9) | |
| Exon 18 G719X | 1 (2.3) | |
| Brain metastasis | Yes | 22 (50.0) |
| No | 22 (50.0) | |
| Lymphangitic metastasis | Yes | 10 (22.7) |
| No | 34 (77.3) | |
| Diagnostics for MET amplification | FISH test | 38 (86.4) |
| Plasma ctDNA NGS | 6 (13.6) | |
| Prior EGFR-TKI | 1st or 2nd generation | 31 (70.5) |
| 3rd generation | 13 (29.5) | |
| EGFR-TKI | 1st or 2nd generation | 9 (20.5) |
| 3rd generation | 35 (79.5) | |
| MET-TKI | Savolitinib | 31 (70.5) |
| Crizotinib | 11 (25.0) | |
| Capmatinib | 2 (4.5) |
ECOG, Eastern Cooperative Oncology Group; PS, performance status; FISH, fluorescence in situ hybridization; ctDNA, circulating tumor DNA; NGS, next-generation sequencing; TKI, tyrosine kinase inhibitor.