Tumor Cells, Tumor DNA and Immunological Response in Colonic Stent Placement

This study aims to investigate levels of circulating cell free DNA (cfDNA), circulating tumor DNA (ctDNA), circulating tumor cells (CTC) and immunological changes after self-expanding metal stent (SEMS) placement for malignant obstruction in the colon, and interpret these levels in relation to overall- and disease-free survival. Furthermore, we intend to study the opportunity to identify patients with a higher risk of recurrence due to the SEMS placement by monitoring cfDNA and ctDNA-levels, as it may be a potential biomarker to initiate or optimize chemotherapy and thereby ensure a better prognosis for the patients.