Grinshpun A, Tsuji J, Li T, Russo D, Anderson L, Rees R, Cibulskis C, Leshchiner I, Stewart C, Tung N, Krop I, Winer E, Tolaney S, Getz G, Jeselsohn R. Longitudinal circulating tumor DNA (ctDNA) whole-exome sequencing (WES) in the phase Ib/II trial of palbociclib and bazedoxifene reveals genomic dynamics and clonal evolution with the acquisition of treatment resistance in hormone receptor-positive, HER2-negative (HR+ HER2-), advanced breast cancer (ABC). Journal Of Clinical Oncology 2022, 40: 1058-1058. DOI: 10.1200/jco.2022.40.16_suppl.1058.Peer-Reviewed Original Research