Table 3 Treatment outcome to afatinib and resistance mechanism identified at disease progression
Treatment outcome | Total number of patients (n = 85) |
|---|---|
Best tumor response, No. (%) | |
 Complete response | 2 (2.4) |
 Partial response | 63 (74.1) |
 Stable disease | 16 (18.8) |
 Progressive disease | 4 (4.7) |
Disease progression site, No. (%) | |
 None | 29 (34.1) |
 New brain lesions | 7 (8.2) |
 New lesions at other sites | 49 (57.6) |
Investigation for resistance mechanism, No. (%) | |
 No progression | 29 (34.1) |
 Not investigated | 25 (29.4) |
 Investigated | 31 (36.5) |
  -Exon 20 T790 M mutation detected | 13 (42.0) |
  -Exon 20 T790 M mutation not detected and no histologic transformation | 18 (58.0) |