Table 1.
Hotspots of PIK3CA mutations in breast cancer
| Exon | Mutation | Number | Frequency (%) | Total number |
|---|---|---|---|---|
| 1 | R108del, R109del | 1, 2 | 1.6, 3.1 | 3 |
| 4 | N345K, N347T (new), D350N | 3,1,1 | 4.7, 1.6, 1.6 | 5 |
| 7 | G451_D454del (new), p.L456V (new) | 1,1 | 1.6, 1.6 | 2 |
| 9 | E542K, E545K, Q546K, Q546R | 6, 11, 1, 1 | 9.4, 17.2 | 19 |
| 13 | E726K | 2 | 3,1 | 2 |
| 20 | D1029H, N1044K, H1047L, H1047R, G1049R | 1, 1, 3, 31, 1 | 1.6, 1.6, 48.4, 4.7, 1.6 | 37 |
| total: 68 |
Using semiconductor NGS, we identified a total of 68 non-silent mutations in 186 breast cancer samples (34.4 %). The most frequent aberrations were p.H1047R, p.E545K, and p.E542K