We hypothesized that PHGR1 may serve as a clinically useful biomarker for detection of lymph node metastasis in colorectal cancer patients because of our observation that PHGR1 mRNA levels are high in normal colon mucosa and very low in normal lymph nodes and several other tissues (Fig. 2a). Here, PHGR1 is linked to metastatic malignant neoplasm in the lymph nodes.