Inavolisib, a selective PI3Kα inhibitor, combined with palbociclib and fulvestrant, has demonstrated significant clinical benefit in PIK3CA-mutated hormone receptor–positive/human epidermal growth factor receptor 2–negative (HR+/HER2−) advanced or metastatic breast cancer (ABC/MBC). This evidence concerns the gene NR4A1 and aneurysmal bone cyst.