BACKGROUND: Esophageal adenocarcinoma is currently the most rapidly increasing cancer in Western populations. L1 (CD171), a neural cell adhesion molecule, has an essential function in tumor progression and has been shown to be expressed in the proliferating cells of the intestinal crypts in mice. The aim of the current study was to determine L1 expression in esophageal cancer and to evaluate whether L1 could serve as a potential marker and therapeutic target for this tumor type. MATERIALS AND METHODS: L1 expression was assessed on a tissue microarray with 257 surgically resected esophageal cancer samples by immunohistochemistry with a monoclonal antibody (Clone UJ127). L1 expression was correlated with clinicopathological data. RESULTS: L1 was detected in 22 (9%) of 257 esophageal cases, whereas 235 (91%) were L1 negative. Nineteen (86%) of the 22 L1-positive cases were adenocarcinoma. Cross table analysis showed a significant association between L1 expression and adenocarcinoma subtype (p
