Likewise, the analysis of hMAM (human mammaglobin A), the most widely studied marker after CK19 (cytokeratin 19) in breast cancer patients, gene expression identifies patients with nearly 100% specificity at the same sensitivity as CK19 (1 tumor cell in 106 peripheral blood mononuclear cells) [19,20]. Here, SCGB2A2 is linked to neoplasm.