Table 1.
Patient characteristics
| Total | 1st TKI | 1st RT | |||||
|---|---|---|---|---|---|---|---|
| Characteristics | N = 104 | % | N = 65 | % | N = 39 | % | P‐value |
| Sex | 1.000 | ||||||
| Male | 37 | 36% | 24 | 37% | 14 | 36% | |
| Female | 67 | 64% | 41 | 63% | 25 | 64% | |
| Age, median (range, years) | 67 | (36–91) | 67 | (36–86) | 71 | (41–91) | 0.3866 |
| Body height, median (range, cm) Bodyweight median (range, kg) |
157 51 |
(130–180) (33–87) |
156 49 |
(130–180) (34–87) |
158 52 |
(130–170) (33–69) |
0.7262 0.9162 |
| Smoking history | 0.8374 | ||||||
| Never smoker | 61 | 59% | 39 | 60% | 22 | 56% | |
| ECOG performance status | 0.8468 | ||||||
| 0–1 | 66 | 63% | 43 | 66% | 23 | 59% | |
| 2 | 20 | 19% | 11 | 17% | 9 | 23% | |
| 3 | 16 | 15% | 10 | 15% | 6 | 15% | |
| 4 | 2 | 2% | 1 | 2% | 1 | 3% | |
| Stage | 0.0003 | ||||||
| Stage IV | 82 | 79% | 59 | 91% | 23 | 59% | |
| Recurrence after operation or (chemo) radiotherapy | 22 | 21% | 6 | 9% | 16 | 41% | |
| Pathology | 0.1383 | ||||||
| Adeno | 102 | 98% | 65 | 100% | 37 | 95% | |
| Adenosquamous | 2 | 2% | 0 | 0% | 2 | 5% | |
| Number of BMs | 0.8683 | ||||||
| 1 | 32 | 31% | 21 | 32% | 12 | 31% | |
| 2 | 17 | 16% | 9 | 14% | 8 | 21% | |
| 3 | 6 | 6% | 4 | 6% | 2 | 5% | |
| 4 | 8 | 8% | 6 | 9% | 2 | 5% | |
| 5≤ | 41 | 39% | 25 | 38% | 15 | 38% | |
| Size of the largest BM, median (range, mm) | 12 | (3–57) | 9 | (3–55) | 22 | (6–57) | <0.001 |
| Initial brain symptom | 0.0001 | ||||||
| Symptomatic | 30 | 29% | 10 | 15% | 20 | 51% | |
| Asymptomatic | 74 | 71% | 55 | 85% | 19 | 49% | |
| Primary leptomeningeal carcinomatosis | 1.0000 | ||||||
| Yes | 8 | 8% | 5 | 8% | 3 | 8% | |
| No | 96 | 92% | 60 | 92% | 36 | 92% | |
| Extracranial metastasis | 0.2481 | ||||||
| Yes | 77 | 74% | 51 | 78% | 26 | 67% | |
| No | 27 | 26% | 14 | 22% | 13 | 33% | |
| DS‐GPA | 0.5859 | ||||||
| 0 | 11 | 11% | 6 | 9% | 5 | 13% | |
| 0.5 | 17 | 16% | 12 | 18% | 5 | 13% | |
| 1 | 21 | 20% | 15 | 23% | 6 | 15% | |
| 1.5 | 18 | 17% | 12 | 18% | 6 | 15% | |
| 2 | 17 | 16% | 7 | 11% | 10 | 26% | |
| 2.5 | 8 | 8% | 6 | 9% | 2 | 5% | |
| 3 | 10 | 10% | 6 | 9% | 4 | 10% | |
| 3.5 | 2 | 2% | 1 | 2% | 1 | 3% | |
| EGFR mutation | 0.1383 | ||||||
| Ex 19 deletion | 52 | 50% | 37 | 57% | 15 | 38% | |
| Ex 21 L858R | 47 | 45% | 24 | 37% | 23 | 59% | |
| Ex 18 L861Q | 3 | 3% | 2 | 3% | 1 | 3% | |
| Ex 18 G719X | 2 | 2% | 2 | 3% | 0 | 0% | |
| EGFR TKI | 0.1774 | ||||||
| Gefitinib | 77 | 74% | 53 | 82% | 26 | 77% | |
| Erlotinib | 24 | 23% | 10 | 15% | 12 | 31% | |
| Afatinib | 3 | 3% | 2 | 3% | 1 | 3% | |
| Upfront brain radiotherapy | — | ||||||
| No | 65 | 63% | 65 | 100% | 19 | 49% | |
| STI only | 19 | 18% | 16 | 41% | |||
| WBRT only | 16 | 15% | 4 | 10% | |||
| STI + WBRT | 4 | 4% | |||||
BM, brain metastasis; DS‐GPA, diagnosis‐specific graded prognostic assessment; ECOG, Eastern Cooperative Oncology Group; RT, radiotherapy; STI, stereotactic irradiation; TKI, tyrosine kinase inhibitor; WBRT, whole brain radiotherapy.