Diagnosis of Lymph Node Metastasis in Colorectal Cancer by a Semi-dry Dot-blot Method.

This study aimed to examine whether the semi-dry dot-blot (SDB) method can correctly identify metastasis to lymph nodes in colorectal cancer. A total of 200 dissected lymph nodes from 83 patients with colorectal cancer who underwent surgery between November 2013 and May 2016 were examined. Each lymph node was first examined by SDB using anti-pancytokeratin antibody (AE1/AE3). Pathological Stage I/II patients with a negative reaction were further analyzed by SDB using anti-cytokeratin 20 antibody (CK-20) to detect micrometastasis or isolated tumor cells. The sensitivity, specificity, and accuracy of SDB using AE1/AE3 were 91.3%, 100%, and 98.0%, respectively. Five of 99 lymph nodes of pathological Stage I/II patients had a negative reaction to AE1/AE3, but were positive to CK-20, while 3 showed isolated tumor cells. The SDB is a useful diagnostic tool to detect lymph node metastases in colorectal cancer.