Results of a phase 2, open-label, randomized study investigating the efficacy of palbociclib in combination with letrozole compared to letrozole alone as first-line therapy in postmenopausal women with advanced ER-positive and HER2-negative breast cancer (PALOMA-1/TRIO-18) were reported about 2 years ago. The gene discussed is ERBB2; the disease is breast carcinoma.