 Cyclooxygenase-2 COX-2 is involved in prostaglandin E2 PGE2 synthesis and is expressed in epithelial inflammatory conditions and some cancers. We have developed an assay to quantify the major urinary metabolite of PGE2, PGE-M. PGE-M has been previously shown to be elevated in the urine of patients with advanced colorectal neoplasia relative to controls. We recently showed that PGEm was a sensitive and specific marker of Crohns disease activity Accepted for publication at DDW 2006. 