Acute Appendicitis in a Man Undergoing Therapy for Mantle Cell Lymphoma

A 71-year-old man was diagnosed with an aggressive mantle cell lymphoma and was started on six cycles of R-CHOP chemotherapy. Approximately two weeks after starting his first cycle of chemotherapy, he complained of severe right lower quadrant abdominal pain, and an abdominal CT scan demonstrated an enlarged appendix with evidence of contained perforation. The man underwent open appendectomy for acute appendicitis and recovered. The appendectomy specimen was submitted for routine pathological analysis. There was histologic evidence of perforation in association with an inflammatory infiltrate with fibrin adhered to the serosal surface; scattered small lymphoid aggregates were present on the mucosal surface. Although the lymphoid aggregates in the submucosa and lamina propria were rather unremarkable by routine histologic examination, immunohistochemistry revealed the lymphocytes to be predominantly Cyclin D1-overexpressing B cells. To our knowledge, this is the first reported case of acute appendicitis in association with appendiceal involvement by mantle cell lymphoma. 1. Introduction An appendectomy specimen collected in a clinical scenario supportive of acute appendicitis is a common sample received in gross rooms for routine pathology analysis. Indeed, the relative simplicity of the specimen makes it a rite of passage for medical students and new residents first approaching the pathology gross examination. While the pathologic examination of the appendix typically supports the clinical impression of acute appendicitis, routine histopathological analysis plays a crucial role in evaluating for occult pathologic conditions, including neoplasia. Carcinomas are the most frequent neoplasms encountered in the appendix; however, other less frequently encountered neoplasms include carcinoid tumors and lymphomas [1]. Lymphoma involving the appendix in association with acute appendicitis has been rarely described previously, with the majority of cases being Burkitt or large B-cell lymphoma [2–15]. Here we report an unusual example of acute appendicitis presenting in a patient undergoing treatment for mantle cell lymphoma. 2. Case Report A 71-year-old man complained of a two week history of right-sided abdominal pain that started after he began his first round of chemotherapy with R-CHOP with pegfilgrastim for mantle cell lymphoma. He presented to the emergency department (ED) after he developed severe (9 out of 10) right lower quadrant abdominal pain, approximately 17 days after starting chemotherapy. A physical examination in the ED revealed tenderness most