KRT19 and cancer: Similar novel approaches are currently in progress, involving a one-step nucleic acid application (OSNA), which detects metastasis by quantifying the CK19 mRNA levels, irrespectively whether it is expressed or not, by employing direct analysis of the supernatant of the homogenised lymph node prior to mRNA purification and exhibiting also good correlation with the cancer cells of the lymph node [35–38].