CTC-testing after resection of metastases in a patient with metastatic colorectal cancer. CTC positivity: CTC+, dg: diagnosis, G: grade, RAS: group of oncogenes, wt: wild type, RFA: radiofrequency ablation, m: months, cape: capecitabine, pani: panitumumab, FOLFOX/FOLFIRI: chemotherapy regimens (see main text), KRT18/19 (keratins), MUC1 (mucin), VIM (vimentin), genes of chemoresistance: see Table 2.