If dormant tumor cells residing in the bone marrow microenvironment exhibited a more mesenchymal phenotype, this could have important implications on current techniques employed to detect DTCs in the bone marrow of patients, which predominantly detect epithelial markers such as cytokeratins [7], [17], Her2/neu [51], Epcam [52], and Mucin [6]. Here, MUC5AC is linked to neoplasm.