Carcinoembryonic antigen (CEA) expression in human tumors: A tissue microarray study on 15,413 tumors

Abstract Introduction/Objective Carcinoembryonic antigen (CEA; CEACAM5) is a cell surface glycoprotein which constitutes an attractive therapeutic target and serum CEA is used for cancer monitoring. CEA is overexpressed in various cancers, but the reported prevalence data vary considerably for many tumor types. Methods/Case Report To comprehensively determine CEA expression in normal and neoplastic tissues, a tissue microarray containing 15,413 samples from 120 different tumor types and subtypes as well as 76 different normal tissue types were analyzed by immunohistochemistry. Results (if a Case Study enter NA) CEA positivity occurred in 65 of 120 tumor categories including 49 entities with at least one strongly positive case. CEA positivity was most common in colorectal carcinomas (98.7%), other gastrointestinal adenocarcinomas (61.1%-80.3%), medullary carcinomas of the thyroid (96.3%), pulmonary adenocarcinoma (73.7%), mucinous carcinomas of the ovary (79.8%) and the breast (43.2%), squamous cell carcinomas of various sites (30.2%-69.1%), and small cell carcinomas of the lung (64.3%), the urinary bladder (38.9%), and the prostate (50.0%). High CEA expression was linked to high grade (p<0.0001) and invasive growth (p<0.0001) in urothelial carcinoma. Reduced CEA expression was associated with mismatch repair deficiency (p<0.0001) but not with pT and pN stage in colorectal cancer. Conclusion In summary, CEA is abundantly expressed in a broad range of epithelial neoplasms. Our data thus identify various tumor entities where CEA positive cancers might best benefit from CEA serum monitoring and anti- CEA therapies.