Table 2.
EGFR mutations in the Dutch population of advanced non-squamous NSCLC patients by year of diagnosis (A) and molecular diagnostic modality (B).
| A | By Year of Advanced NSCLC Diagnosis | ||||||
| Mutation(s) | Total | 2013 | 2015 | 2017 | p a | ||
| Tested for Mutations, n (%) | 7908 (100) | 2324 (100) | 2643 (100) | 2941 (100) | |||
| Any EGFR mutation | 925 (11.7) | 256 (11.0) | 328 (12.4) | 341 (11.6) | 0.303 | ||
| Distribution of predefined classes of sensitivity | |||||||
| Exon 19 deletion | 393 (5.0) | 104 (4.5) | 142 (5.4) | 147 (5.0) | 0.347 | ||
| L858R | 287 (3.6) | 81 (3.5) | 97 (3.7) | 109 (3.7) | 0.905 | ||
| Exon 20 insertion | 69 (0.9) | 21 (0.9) | 24 (0.9) | 24 (0.8) | 0.917 | ||
| Uncommon, actionable | 103 (1.3) | 24 (1.0) | 41 (1.6) | 38 (1.3) | 0.274 | ||
| Not actionable/unknown | 61 (0.8) | 20 (0.9) | 19 (0.7) | 22 (0.7) | 0.836 | ||
| Not specified | 12 (0.2) | 6 (0.3) | 5 (0.2) | 1 (0.0) | 0.097 | ||
| Distribution of uncommon EGFR mutation(s) | |||||||
| >1 EGFR mutation | 62 (0.8) | 16 (0.7) | 27 (1.0) | 19 (0.6) | 0.233 | ||
| E709X | 12 (0.2) | 4 (0.2) | 6 (0.2) | 2 (0.1) | 0.299 | ||
| G719X | 55 (0.7) | 14 (0.6) | 21 (0.8) | 20 (0.7) | 0.713 | ||
| S768I | 35 (0.4) | 8 (0.3) | 18 (0.7) | 9 (0.3) | 0.076 | ||
| L861X | 29 (0.4) | 5 (0.2) | 9 (0.3) | 15 (0.5) | 0.206 | ||
| B | By Molecular Diagnostic Modality | ||||||
| Mutation(s) | Total | Single-Gene Test(s) | Multi-Gene Assay | p c | |||
| Cases, n (%) | 6308 (100) b | 2350 (100) | 3958 (100) | ||||
| Distribution of predefined classes of sensitivity | |||||||
| Exon 19 deletion | 320 (5.1) | 118 (5.0) | 202 (5.1) | 0.906 | |||
| L858R | 233 (3.7) | 98 (4.2) | 135 (3.4) | 0.129 | |||
| Exon 20 insertion | 57 (0.9) | 24 (1.0) | 33 (0.8) | 0.492 | |||
| Uncommon, actionable | 83 (1.3) | 27 (1.1) | 56 (1.4) | 0.424 | |||
| Not actionable/unknown | 45 (0.7) | 16 (0.7) | 29 (0.7) | 0.878 | |||
| Not specified | 3 (0.0) | 2 (0.1) | 1 (0.0) | 0.560 | |||
| Distribution of individual uncommon EGFR mutation(s) | |||||||
| >1 EGFR mutation | 49 (0.8) | 20 (0.9) | 29 (0.7) | 0.657 | |||
| E709X | 11 (0.2) | 5 (0.2) | 6 (0.2) | 0.551 | |||
| G719X | 45 (0.7) | 15 (0.6) | 30 (0.8) | 0.645 | |||
| S768I | 26 (0.4) | 11 (0.5) | 15 (0.4) | 0.685 | |||
| L861X | 24 (0.4) | 4 (0.2) | 20 (0.5) | 0.036 | |||
Values in bold indicate significant differences. a Level of significance tested with Pearson’s Chi-square test, considered significant at p < 0.05. b Does not include patients for whom the testing modality was not reported (n = 1600). c Level of significance tested with Fisher’s exact test, considered significant at p < 0.05. Abbreviations: EGFR, epidermal growth factor receptor gene; HRM, high-resolution melting; NGS, next-generation sequencing; NOS, not otherwise specified; NSCLC; non-small cell lung cancer; PCR, polymerase chain reaction.