New York-Presbyterian/Weill Cornell Medical Center New York, NY
Rochelle Wong, MD1, James Stulman, MD2, Paul Miskovitz3, Lea Lowenfeld, MD3, David Wan, MD3; 1New York-Presbyterian/Weill Cornell Medical Center, New York, NY; 2Weill Cornell Medicine, New York, NY; 3Weill Cornell Medical College, Cornell University, New York, NY
Introduction: Appendiceal mucocele is a rare disease. The incidence is 0.2-0.4% of all appendectomy specimens.1 It occurs when mucin abnormally accumulates in the appendix, due to non-neoplastic, benign, or malignant conditions. Surgical resection is potentially curative. Here we describe our experience with this rare phenomenon that was correctly diagnosed by computed tomography (CT) imaging prior to surgery.
Methods: A 62-year-old man with no significant medical history presented with 4-weeks of crampy abdominal pain and intermittently bloody and mucous diarrhea. Last colonoscopy four years ago only showed sigmoid diverticulosis. A contrast-enhanced CT abdomen and pelvis showed 7.3cm by 3.4cm mass intussuscepting into the cecum, suspicious for appendiceal mucocele (Fig. 1). Diagnostic laparoscopy showed thickened appendix with terminal ileum intussusception and no evidence of disseminated mucin (Fig. 2). Laparoscopy was converted to open right hemicolectomy to minimize manipulation of the ileocecum (Fig. 3). Pathology revealed low-grade appendiceal mucinous neoplasm (LAMN). Consensus of a multidisciplinary tumor board recommended repeat CT abdomen and pelvis every 6 months and repeat colonoscopy at 1 year to monitor for recurrence. Discussion: Symptomatic appendiceal mucoceles rarely present as intussusception.2 This case highlights the importance of preoperative diagnosis as it can guide surgical management. Benign retention of mucus can effectively be treated with appendectomy, but neoplastic conditions often need more extensive resection to avoid peritoneal implantation.3 The ultimate goal is to avoid spontaneous or iatrogenic rupture leading to disseminated mucinosis and the highly morbid pseudomyxoma peritoneum. Close clinical and radiographic surveillance is recommended within 1-year following surgical resection.4
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Figure 1. Coronal CT view of intussuscepting mass into the cecum, suspicious for appendiceal mucocele.
Figure 2. Diagnostic laparoscopy with large thickened appendix causing intussusception of the terminal ileum into the right colon.
Figure 3. Thickened appendix specimen dissected open with large ecchymotic mass at the base of the appendix, free from ileocecal valve, likely the intussusception lead point.
Disclosures: Rochelle Wong indicated no relevant financial relationships. James Stulman indicated no relevant financial relationships. Paul Miskovitz indicated no relevant financial relationships. Lea Lowenfeld indicated no relevant financial relationships. David Wan indicated no relevant financial relationships.