Table 1.
Clinicopathological characteristics of lung cancer patients with compound EGFR mutations
| Variable | Single common mutation (n = 115) | Compound mutations (n = 106) | P † | Double common mutations (n = 5) | P † | Common + rare mutations (n = 11) | P † | Rare + rare mutations (n = 13) | P † | Rare + T790M mutations (n = 8) | P † | Common + T790M mutations (n = 69) | P † |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sex | |||||||||||||
| Female | 56 | 55 | 0.635 | 1 | 0.368 | 6 | 0.711 | 6 | 0.862 | 4 | 0.943 | 38 | 0.402 |
| Male | 59 | 51 | 4 | 5 | 7 | 4 | 31 | ||||||
| Age (years) | |||||||||||||
| < 60 | 57 | 63 | 0.141 | 2 | 0.675 | 5 | 0.794 | 8 | 0.413 | 7 | 0.063 | 41 | 0.195 |
| ≥ 60 | 58 | 43 | 3 | 6 | 5 | 1 | 28 | ||||||
| Smoking status | 0.270 | 0.118 | 0.795 | 0.442 | 0.795 | 0.022 | |||||||
| Non-smoker | 69 | 69 | 1 | 5 | 4 | 5 | 54 | ||||||
| Smoker | 34 | 24 | 3 | 3 | 4 | 3 | 11 | ||||||
| Unknown | 12 | 13 | 1 | 0 | 5 | 0 | 4 | ||||||
| Tumour status | 0.034 | 0.592 | 0.782 | 0.753 | 0.103 | 0.064 | |||||||
| Recurrence | 36 | 20 | 1 | 3 | 3 | 0 | 13 | ||||||
| Initial IIIb–IV | 79 | 86 | 4 | 8 | 10 | 8 | 56 | ||||||
| ECOG PS | |||||||||||||
| 0–1 | 107 | 96 | 0.501 | 4 | 0.327 | 9 | 0.212 | 13 | 0.326 | 6 | 0.071 | 64 | 0.941 |
| 2–4 | 8 | 10 | 1 | 2 | 0 | 2 | 5 | ||||||
| Pathology | 0.529 | 0.141 | 0.672 | 0.899 | 0.948 | 0.534 | |||||||
| ADC | 110 | 102 | 4 | 10 | 13 | 8 | 67 | ||||||
| SCC | 5 | 2 | 0 | 1 | 0 | 0 | 1 | ||||||
| LELC | 0 | 1 | 1 | 0 | 0 | 0 | 0 | ||||||
| ASC | 0 | 1 | 0 | 0 | 0 | 0 | 1 | ||||||
| Timing of TKI | 0.720 | 0.914 | 0.835 | 0.803 | 0.805 | 0.460 | |||||||
| First line | 52 | 55 | 2 | 5 | 6 | 3 | 39 | ||||||
| Second line | 55 | 46 | 3 | 6 | 7 | 5 | 25 | ||||||
| Third line | 7 | 4 | 0 | 0 | 0 | 0 | 4 | ||||||
| Fourth line | 1 | 1 | 0 | 0 | 0 | 0 | 1 | ||||||
| TKI selection | 0.034 | 0.981 | 0.592 | 0.214 | 0.161 | 0.021 | |||||||
| Gefitinib | 64 | 47 | 3 | 5 | 4 | 2 | 33 | ||||||
| Erlotinib | 26 | 41 | 1 | 4 | 4 | 4 | 28 | ||||||
| Icotinib | 25 | 18 | 1 | 2 | 5 | 2 | 8 | ||||||
| Response to TKIs | |||||||||||||
| PD | 10 | 14 | 0.088 | 1 | 0.148 | 2 | 0.652 | 2 | 0.328 | 4 | 0.012 | 5 | 0.293 |
| SD | 21 | 33 | 1 | 3 | 5 | 1 | 22 | ||||||
| PR | 77 | 54 | 3 | 5 | 5 | 3 | 39 | ||||||
| CR | 1 | 0 | 0 | 0 | 0 | 0 | 0 | ||||||
| NE | 6 | 5 | 0 | 1 | 1 | 0 | 3 | ||||||
ECOG PS Eastern Cooperative Oncology Group performance status, ADC adenocarcinoma, SCC squamous cell carcinoma, LELC lymphoepithelioma-like carcinoma, ASC adenosquamous carcinoma, PD progressive disease, SD stable disease, PR partial response, CR complete response, NE not evaluated, TKI tyrosine kinase inhibitor, PFS progression-free survival, OS overall survival
†All variables of different subgroups were compared with the single common mutation group; P < 0.05 was defined as significantly different