Clinical characteristics of EGFR mutant patients treated with epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs)
| Total patients | Age ≤50 years | Age >50 years | p-value | |
| Subjects | 524 | 81 (15.5) | 443 (84.5) | |
| Age years | 64.7 (29.5–92.1) | 43.9 (29.5–49.6) | 68.1 (50.1–92.1) | |
| Sex | 0.405 | |||
| Female | 308 | 51 (63.0) | 257 (58.0) | |
| Male | 216 | 30 (37.0) | 186 (42.0) | |
| Smoking history | 0.010 | |||
| Never-smoker | 419 | 62 (76.5) | 357 (80.6) | |
| Ex-smoker | 52 | 4 (4.9) | 48 (10.8) | |
| Current smoker | 53 | 15 (18.5) | 38 (8.6) | |
| ECOG PS | 0.002# | |||
| 0–1 | 449 | 78 (96.3) | 371 (83.7) | |
| 2–4 | 75 | 3 (3.7) | 72 (16.3) | |
| EGFR mutation | 0.009 | |||
| Del-19 | 233 | 33 (40.7) | 200 (45.1) | |
| L858R | 228 | 30 (37.0) | 198 (44.7) | |
| Uncommon | 63 | 18 (22.2) | 45 (10.2) | |
| EGFR-TKI | 0.051 | |||
| Gefitinib | 366 | 51 (63.0) | 315 (71.1) | |
| Erlotinib | 137 | 23 (28.4) | 114 (25.7) | |
| Afatinib | 21 | 7 (8.6) | 14 (3.2) | |
| TKI sequence | 0.140 | |||
| First-line | 339 | 49 (60.5) | 290 (65.5) | |
| Second-line | 117 | 16 (19.8) | 101 (22.8) | |
| Third-line or greater | 68 | 16 (19.8) | 52 (11.7) |
Data are presented as n, n (%) or median (range), unless otherwise stated. ECOG PS: Eastern Cooperative Oncology Group performance status. #: Fisher's exact test.