Cytokeratin negative CTC from breast cancer patients have been described to express the EMT related antigens vimentin and fibronectin [51] and breast cancer patients negative for hormone receptors, high tumor grade, triple-negative disease or inflammatory breast cancer had increased probabilities for being undetectable by CellSearch, possibly due to CTC undergoing EMT [52]. The gene discussed is NR4A1; the disease is breast carcinoma.