KRT19 and colorectal cancer: The one-step nucleic acid amplification (OSNA) method quantifies cytokeratin 19 (CK19) mRNA expression, and is used in clinical practice for the diagnosis of LNM in several types of tumors, such as breast [3], gastric [4] or colorectal cancer [5], and recently in prostate [6] and gynaecological malignancies [7].