<i>ESR1</i> ctDNA testing: literature review and comparison of assays for <i>ESR1</i> mutation detection in advanced hormone receptor-positive breast cancer

A range of commercial assays are available for <i>ESR1</i>m detection in liquid biopsies from patients with HR-positive/HER2-negative ABC, and more are in development, with increasing clinical demand. qPCR, dPCR, and NGS assays can detect common <i>ESR1</i>m with differing sensitivity and specificity depending on the assay and amount of input DNA. Assay selection will vary depending on analytical performance, turnaround times, lab infrastructure and expertise, healthcare setting, and regional variation in market costs.