Table 3.
Somatic gene alterations identified
| Gene | Exon | Mutations identified -- no. (%) |
|---|---|---|
| EGFR a | --- | 60 (100)b |
| 18 | G719A: 2 (3); G719C: 1 (2); G719S: 1 (2) | |
| 19 | deletions: 13 (22); deletion-insertions: 8 (13) L747P (cis) or L747L/L747S (trans)c: 2 (3) |
|
| 20 | duplications: 4 (7); insertions: 2 (3); deletion-insertions: 1 (2); deletions: 1 (2) T790M: 2 (3); S768I: 1 (2) |
|
| 21 | L858R: 20 (33); L861Q: 2 (3) | |
| KRAS a | --- | 79 (100)d |
| 2 | G12C: 30 (38); G12D: 18 (23); G12V: 11 (14); G12A: 7 (9); G12S: 3 (4) G12F (cis) or G12C/G12V (trans)e: 1 (1); G12L (cis) or G12R/G12V (trans)f: 1 (1) G13C: 1 (1); G13D: 1 (1) |
|
| 3 | Q61H: 4 (5); Q61K: 1 (1) | |
| BRAF | --- | 16 (100) |
| 11 | G466V: 1 (6); G466R: 1 (6); G469A: 1 (6); G469del: 1 (6) | |
| 15 | V600E: 9 (56); D594N: 1 (6); D594G: 1 (6) T599_V600insT: 1 (6) |
|
| HER2 | --- | 15 (100) |
| 20 | duplications: 9 (60); insertions: 3 (20): deletion-insertions: 2 (13) V777L: 1 (7) |
|
| PIK3CA a | --- | 6 (100) |
| 8 | E453_P458delinsD: 1 (17) | |
| 10 | E542K: 3 (50) | |
| 21 | H1047R: 2 (33) | |
| ALK | --- | 16 (100) Rearrangement: FISH-positive, 12 (75); IHC-only positive, 4 (25) |
Three specimens harbored concurrent mutations in PIK3CA and either KRAS (n=2) or EGFR (n=1).
Four specimens had two concurrent EGFR mutations.
Two specimens had two DNA sequence variants in EGFR: 2239T>C and 2240T>C. If these two variants occur on the same allele (cis), the expected amino acid change is L747P. If these two variants occur on separate alleles (trans), the expected amino acid changes are L747L and L747S.
One specimen was tested at an outside facility and reported as positive for a KRAS mutation but information on the specific amino acid change was not available.
Two DNA sequence variants were detected in KRAS: 34G>T and 35G>T. If these variants occur on the same allele, the expected amino acid change is G12F. If these variants occur on separate alleles, the expected amino acid changes are G12C and G12V.
Two DNA sequence variants were detected in KRAS: 34G>C and 35G>T. If these variants occur on the same allele, the expected amino acid change is G12L. If these variants occur on separate alleles, the expected amino acid changes are G12R and G12V.