Performance of a high-intensity 508-gene circulating-tumor DNA (ctDNA) assay in patients with metastatic breast, lung, and prostate cancer

Background

  • ctDNA assays can noninvasively assess tumor burden and biology by identifying tumor-derived somatic alterations.
  • To date, ctDNA studies have focused primarily on detecting driver mutations to inform treatment strategies in advanced disease or monitoring disease burden in patients with established cancer diagnoses. Platforms used for these purposes target individual variants or limited genomic regions informed by sequencing of tumor tissue. (Wan 2017)
  • Analysis of plasma cell-free DNA may enable early cancer detection in previously undiagnosed individuals but will require de novo variant calling (in the absence of tissue) as well as sufficient genomic coverage to address the spectrum of variant profiles that are cancer-defining. (Aravanis 2017)
  • We propose that a high-intensity approach (ultra-deep sequencing of plasma cell-free DNA with broad genomic coverage) will add a new dimension to our understanding of intra-patient and population-level heterogeneity.