Adenocarcinoma of Appendix Mimicking Acute Appendicitis

Introduction: Acute appendicitis is one of the most common causes of acute abdomen. Obstruction of the lumen of the appendix due to fecolith, lymphoid hyperplasia and tumors can cause appendicitis. Appendicular tumors are rare, with carcinoids being the most common. Adenocarcinoma accounts for only 0.5% of all GI cancers, and for 0.05-0.2% of all appendectomies. Peak incidence is around 6th decade. Here we present one such case of adenocarcinoma of appendix presenting as acute appendicitis.

Materials and Methods: A 69-yearold male patient presented with complaints of right lower quadrant abdominal pain. He had a previous history of ERCP and CBD stent placement for cholangiocarcinoma. On examination, he had right iliac fossa tenderness. No icterus. Patient was evaluated with USG abdomen and pelvis, which showed inflamed appendix, 6.8mm in caliber. Patient was taken up for surgery and open appendectomy was done. Specimen was sent for histopathology. Perioperative period was uneventful.

Results: On histopathology, the external surface of the appendix was unremarkable. Cut section revealed obliterated lumen with tip of appendix showing mass of 2x1 cm. Individual cells arranged in glandular pattern with high N:C ratio, features suggestive of adenocarcinoma of appendix-metastatic/primary.

Conclusion: Adenocarcinomas are usually diagnosed postoperatively on histopathology. Although rare, it should be considered as one of the causes of acute appendicitis in the elderly. All appendectomy specimens should be sent for histopathology. Once diagnosed as adenocarcinoma, a right hemicolectomy is the preferred surgery.