Table 2.
Pooled discordance rates according to direction of PIK3CA mutational status change and within subgroups of interest
| Parameters | N studies (n pairs) | Pooled discordance, % | 95% Confidence Interval, % | Statistical heterogeneity (I2) | p-value for comparison |
|---|---|---|---|---|---|
| Direction of change | 0.003 | ||||
| Mut to wild-type | 24 (453) | 14.9 | 11.8–18.2 | 35.3 | |
| Wild type to mut | 24 (943) | 8.9 | 6.1–12.1 | 56.4 | |
| Breast cancer subtype | 0.577 | ||||
| HR + /HER2-negative | 13 (583) | 10.2 | 6.4–14.8 | 56.6 | |
| HER2-positive | 10 (149) | 8.7 | 4.8–13.7 | 0.0 | |
| TNBC | 11 (151) | 8.8 | 4.9–13.7 | 0.0 | |
| Site of recurrence | 0.839 | ||||
| Locoregional | 8 (306) | 9.6 | 6.6–13.1 | 29.0 | |
| Distant (any) | 11 (301) | 9.9 | 6.8–13.5 | 49.4 | |
| Metastatic site | 0.330 | ||||
| Brain | 5 (106) | 9.6 | 1.1–24.9 | 77.2 | |
| Liver | 3 (59) | 6.4 | 1.7–13.9 | 0.0 | |
| Other | 5 (67) | 11.2 | 4.9–19.6 | 7.2 | |