Pathological Discrepancy: Simple Mesenteric Cyst vs. Mesenteric Lymphangioma

INTRODUCTION: Both mesenteric cysts and cystic lymphangiomas are scarce and clinically and radiologically almost identical derivatives, but their histological structure is fundamentally different. Case Presentation. A 52-year-old woman was consulted by a surgeon for a derivative felt in her abdomen. The patient said she felt a growing derivative in the abdomen about a month ago. After consulting and testing, a sigmoid colon mesenteric cyst (13 cm × 11 cm × 10 cm) was found. Complete excision of the cyst within healthy tissues was performed through laparotomy. The surgery had no complications. The initial pathological answer was a simple mesothelial cyst (a rare histological finding). However, immunohistochemical tests were performed that showed that diagnosis was mesenteric cystic lymphangioma (ML). Cystic lymphangiomas that have a link to the mesentery have been described less than 200 times. CONCLUSIONS: Final differential diagnosis between different cystic derivatives is possible only based on histopathological examinations. Mesenteric lymphangioma is most common at a very young age, but in rare cases, it also occurs in adults. All clinicians should increase their awareness of the disease.