KRT19 and malignant colon neoplasm: In most publications that tested OSNA for the detection of lymph node micrometastases and macrometastases, the cutoff was set at 250 CK19 mRNA copies/μL.13, 17, 19, 20 Although some of those investigations were performed in patients with breast cancer, the results of the molecular analyses are transferable to the setting of patients with colon cancer.