FIGURE 7.

Newly detected circulating tumor DNA (ctDNA) alterations at disease progression linked to resistance. Arrows indicate the direction of pathway cascades leading to cell cycle checkpoint regulation. “Acquired variants” were ctDNA that were undetected within the first cycle of cyclin‐dependent kinase 4/6 (CDK4/6) inhibitor treatment (single nucleotide variant [SNV] count = 0 or copy number variant [CNV] = 2.0‐fold) and detected at disease progression (SNV ≥0.2% or CNV ≥2.5‐fold). Variant allele frequencies (VAF) or copy numbers of paired pretreatment and progressive disease (PD) time points are listed in the colored boxes directly below the detected variants