P-300Predictive value of circulating tumor-derived DNA (ctDNA) in patients with locally advanced rectal cancer (LARC) treated with neoadjuvant chemoradiotherapy (CT-RT): Preliminary results

Introduction: In patients with LARC, neoadjuvant CT-RT followed by curative surgery is the standard of care. Risk-adopted treatment is based on MRI-predicting local T and N stage, radial margins and vascular involvement while no molecular predictive markers are available. In the present prospective study, we investigated the predictive role of serum ctDNA in patients with LARC.