Retroperitoneal mucocele of the appendix: diagnosis and management

Abstract

Introduction: Appendiceal mucocele is an interesting pathology, given its rarity and its tricky management. The retroperitoneal localization is even more interesting because of its difficulties to diagnosis and treat. Indeed, in case of mucocele is incorrectly treated, pseudomyxoma peritonei may develop, secondary to an intraperitoneal rupture of the mass. Case report: We present here the case of a 50-year-old woman who consulted for a mild right low back pain with palpable abdominal mass. A CT-scan performed showed a large right retroperitoneal mass evoking a retroperitoneal cystic lymphangioma. The patient underwent an exploratory laparotomy, which showed a large whitish retroperitoneal cyst, extending from the right iliac fossa to the right hypochondrium. We suspected during surgery an appendiceal mucocele. During dissection, we assisted to a tumoral rupture. The peritoneal cavity was already protected by surgical drape. We went an en-bloc and complete resection of the tumor. The histological study concluded to a mucinous cystadenoma. After a one-year follow-up, control CT-scans showed no signs of recurrence. Conclusion: Retroperitoneal appendiceal mucocele is a rare disease. A correct radiological pre-operative diagnosis, based on CT-scan, is important to avoid severe intraoperative complications.

A retroperitoneal cyst arising from an appendix fragment

“…Cystic retroperitoneal lesions are rare with an incidence of three cases for every million hospital admissions 1 and include a variety of differentials such as cystic lymphangioma, mucinous cystadenoma, cystic teratoma and pseudomyxoma retroperitonea 2 . Large retroperitoneal masses are typically not associated with appendiceal lesions but there have been cases of appendiceal masses mimicking retroperitoneal lesions 3 . Mucinous neoplasms of the appendix are rare, representing 0.2%–0.3% of appendicectomy specimens 4 and most of them arise from LAMN 5 .…”