3. Diéras V, Harbeck N, Joy AA, Gelmon K, Ettl J, Verma S, et al. Palbociclib with Letrozole in Postmenopausal Women with ER+/HER2- Advanced Breast Cancer: Hematologic Safety Analysis of the Randomized PALOMA-2 Trial. Oncologist. 2019;24:1514-25. Here, ESR1 is linked to breast cancer.