L1CAM and gastrointestinal stromal tumor: Studies have shown that L1CAM is highly expressed in certain tumor tissues, but not in all tumor tissues, and is limited to certain tumors or subtypes of certain tumors, such as L1CAM is high expression in gastrointestinal stromal tumors (GIST) and uterine and ovarian cancers, but low expression in esophageal squamous cell carcinoma (ESCC) 22,24,25.