PIK3CA alterations were found in 43.5% of HR+/HER2- tumours (n = 47), 50% of HER2-enriched lesions (n = 2), 33.3% of HR+/HER2+ (n = 3) and 11.1% of TNBCs (n = 5) (Fig. 2a). This evidence concerns the gene ERBB2 and neoplasm.