Epithelial cell adhesion molecule (EPCAM) is a transmembrane glycoprotein mediating Ca2+-independent homotypic cell-cell adhesion in epithelia. EPCAM is also involved in cell signaling, migration, proliferation, and differentiation. Additionally, EPCAM has oncogenic potential via its capacity to upregulate c-myc, e-fabp, and cyclins A & E. Since EPCAM is expressed exclusively in epithelia and epithelial-derived neoplasms, EPCAM can be used as diagnostic marker for various cancers. It appears to play a role in tumorigenesis and metastasis of carcinomas, so it can also act as a potential prognostic marker and as a potential target for immunotherapeutic strategies.