Table 1.
Patient and treatment characteristics.
| All | BS | No BS | P-value | |
|---|---|---|---|---|
| No. of cases | 100 | 40 | 60 | |
| Mean Age (years ± SD) | 60 ± 10 | 61 ± 9 | 60 ± 11 | 0.643 |
| Sex | 0.799 | |||
| Female | 64 | 25 | 39 | |
| Male | 36 | 15 | 21 | |
| Initial Clinical stage | 0.775 | |||
| I-II | 9 | 4 | 5 | |
| III-IV | 91 | 36 | 55 | |
| Initial Tumor classification | 0.78 | |||
| 1 or 2 | 26 | 11 | 15 | |
| 3 or 4 | 74 | 29 | 45 | |
| Initial Nodal classification | 0.239 | |||
| 0 or 1 | 38 | 18 | 20 | |
| 2 or 3 | 62 | 22 | 40 | |
| Extracranial metastases | ||||
| Bone | 72 | 26 | 46 | 0.203 |
| Lung | 38 | 15 | 23 | 0.933 |
| Liver | 15 | 3 | 12 | 0.086 |
| Histological grade | 0.119 | |||
| 1–2 | 40 | 15 | 25 | |
| 3 | 23 | 6 | 17 | |
| NA | 37 | 19 | 18 | |
| EGFR mutation | ||||
| Exon 18 | 1 | 0 | 1 | 0.6 (Fisher) |
| Exon 19 | 46 | 24 | 22 | 0.022 |
| Exon 20 | 8 | 5 | 3 | 0.164 (Fisher) |
| Exon 21 | 40 | 11 | 29 | 0.037 |
| NA | 6 | 1 | 5 | 0.397 (Fisher) |
| RT mean boost dose (cGy ± SD) | 3779 ± 748 | 3908 ± 612 | 3694 ± 821 | 0.163 |
| dose >3750 cGy | 39 | 17 | 22 | |
| dose ≦3750 cGy | 61 | 23 | 38 | |
| Number of lines of systemic chemotherapy | 0.518 (Fisher) | |||
| 0–3 | 89 | 37 | 52 | |
| >3 | 11 | 3 | 8 | |
| TKI name | ||||
| afatinib | 12 | 8 | 4 | 0.044 (Fisher) |
| erlotinib | 57 | 22 | 35 | 0.742 |
| gefitinib | 64 | 21 | 43 | 0.05 |
| osimertinib | 5 | 1 | 4 | 0.332 (Fisher) |
| Number of lines of TKI | 0.447 | |||
| 1 | 63 | 27 | 36 | |
| >1 | 37 | 13 | 24 | |
| Mean TKI use duration (months ± SD) | 19.2 ± 16.8 | 18 ± 14 | 20 ± 18.5 | 0.585 |
| ECOG performance status | 0.736 | |||
| 0 | 52 | 19 | 33 | |
| 1 | 44 | 19 | 25 | |
| 2 | 4 | 2 | 2 | |
| Smoking status | 0.182 | |||
| Never | 77 | 27 | 15 | |
| Former | 9 | 5 | 4 | |
| Current | 14 | 8 | 6 | |
| Symptomatic BM | 0.168 | |||
| No | 22 | 6 | 16 | |
| Yes | 78 | 34 | 44 | |
| Size of the largest BM | 0.001 | |||
| ≦1 cm | 28 | 4 | 24 | |
| >1 cm | 72 | 36 | 36 | |
| Number of BM | 0.137 | |||
| 1 | 18 | 10 | 8 | |
| >1 | 82 | 30 | 52 | |
| dsGPA | 0.373 | |||
| 0.5–1.5 | 70 | 26 | 44 | |
| 2–4 | 30 | 14 | 16 |
Abbreviations: BS: brain surgery; EGFR: epidermal growth factor receptor; RT: radiation therapy; TKI: tyrosine kinase inhibitor; ECOG: Eastern Cooperative Oncology Group; BM: brain metastasis; dsGPA: disease-specific Graded Prognostic Assessment.