P-253 Monitoring circulating epithelial tumor cells (CETCs) in patients with locally advanced colorectal cancer during therapy as a tool to predict therapy response

Abstract

Since the first results of the CAO/ARO/AIO-94 trial were published, a combination of neoadjuvant therapy with subsequent total mesorectal excision (TME) has been established as a standard treatment for patients suffering from locally advanced (stage II and III) rectal cancer. Replacing the postoperative by a preoperative (chemo-) radiotherapy (C/RT) led to an impressive improvement in the rates of local tumor recurrence (6% vs 13%) and of toxicity (27% vs 40%). Significant decreases in metastatic relapses, the main reason for therapy failure, have not been achieved, resulting in a poorer outcome in patients with rectal vs colon cancer.