CDK4 and breast carcinoma: For HR‐positive/HER2‐negative advanced breast cancer patients with PIK3CA mutation who had received CDK4/6 inhibitor treatment, it is proved by the BYLieve study [33] for the first time that they can benefit from alpelisib treatment in combination with aromatiase inhibitors (AI), with the efficacy and safety profile unaffected by alpelisib.