Prognostic value of baseline and early changes of circulating-free (cf) and circulating tumor (ct) DNA in the neoadjuvant (NA) setting of early stage colon cancer (CC).

3600 Background: ctDNA is an indicator of minimal residual disease and negative prognostic factor in stage II-III CC treated with surgery +/- adjuvant chemotherapy (CT). No study, however, has ever analysed the prognostic value of this biomarker in CC patients (pts) treated with NACT. We sought to evaluate the prognostic value of baseline and early changes of cf/ctDNA in stage II-III CC pts who were treated with one cycle of NA FOLFOX CT...