PIK3CA and breast cancer: This may be, at least in part, attributed to already implemented routine molecular diagnostics tests (i.e., companion diagnostics), e.g., BRCA1/2, PIK3CA, or ERBB2/HER2 mutation screening for breast cancers and the introduction of a lung cancer-specific gene panel on site in 2018 [37], which facilitates the detection of therapeutically relevant alterations in these entities before patient inclusion in the MTB becomes necessary.