Cell-free DNA and preoperative chemoradiotherapy for rectal cancer: a systematic review.

Abstract

Preoperative chemoradiotherapy is the standard of care for patients with locally advanced rectalcancer, yet valid circulating biomarkers are lacking. We aimed at systematically reviewing the literature of cell-free DNA and locally advanced rectal cancer. A systematic literature search was performed. We retrieved papers reporting a correlation between a clinical outcome and cell-free DNA for patients receiving chemoradiotherapy for locally advanced rectal cancer. We included nine studies of a total of 615 patients. Only single-arm studies were identified, analyzing either the total level of cell-free DNA or tumor-specific DNA. Despite differences in the methodology and outcomes, eight of the nine studies showed a correlation between cell-free DNA and a clinical outcome. Cell-free DNA might hold prognostic and predictive information for patients with locally advanced rectal cancer receiving preoperative chemoradiotherapy; although, firm conclusions are limited by the heterogeneity in this field.