CD274 and colorectal cancer: Here, we optimised a combined protocol in which CTC isolation is performed by the IsoFluxTM (Fluxion, Biosciences, Inc., Alameda, CA, USA) technology, followed by phenotypic characterisation using the ImageStream®X (Luminex, Belgium) platform for the joint evaluation of BRAFV600E and PD-L1 expression on CTCs from early-stage colorectal cancer patients.