
This 39 y/o male presented to the ER with vague right lower quadrant pain and tenderness of several days duration, T - 100.2 °F, WBC - 10,300 /cc3. Abdomino-pelvic CT with rectal contrast was performed. Appendicitis and inflammatory bowel disease were considered in the differential diagnosis. At surgery mucinous adenocarcinoma of the appendix with spread to the adjacent mesentery and peritoneal surfaces was found.