Table 4.
Comparisons of the QCI-I results for chosen CTCs and paired primary tumor samples with reported data on gene variant pathogenicity
| Gene | Variants | Tier | Pathogenicity | Effect | Allelic frequency (%) | |
|---|---|---|---|---|---|---|
|
| ||||||
| CTC | BC8 FFPE | |||||
| BRAF | c.1750C>T, p.L584F | 1A | ü | missense | 0,59 | - |
| PIK3CA | c.241G>A, p.E81K | 2C | ü | missense | 1,01 | - |
| ALK | c.3833A>G, p.Y1278C | 2C | Very Likely | missense | 0,52 | - |
| PIK3CA | c.328G>A, p.E110K | 2C | Very Likely | missense | 1,3 | - |
| PIK3CA | c.3025G>C, p.G1009R | 2C | Very Likely | missense | - | 4,03 |
More mutations were detected in the CTC samples than in the primary tumor samples (BC8), however, variants were generally present at very low frequency (only mutations with ≥ 1% are reported to the clinic). If the frequency is < 1%, the quality of NGS analysis for the specific gene has to be re-evaluated. As shown in the Table, several mutations in the PIK3CA gene occurred.