KRAS and colorectal carcinoma: To further expand the detection limit of single analyte-dependent enrichment (to include more CTC subpopulations during separation), several attempts had been conducted using different CSMs, including KRAS (Kirsten rat sarcoma viral oncogene), pan-cytokeratin (pan-CK), vimentin (VIM), cluster of differentiation (CD2, CD16, CD19, CD36, CD38, CD45, and CD66b), and/or glycophorin A. For instance, Feng and the researchers proposed the use of a lipid magnetic ball coated with KRAS to isolate CTCs from CRC with KRAS mutations.