Mesenteric cysts are rare intra-abdominal benign tumors (1 in 100,000 cases in adults) with various clinical presentations. [1,2] They commonly originate from the small bowel mesentery, although a proportion has been found to originate from the mesocolon, and retroperitoneum. [1,3] The formation of mesenteric cysts depends on the histologic origin, where they could be classified into cysts of lymphatic origin, cysts of mesothelial origin, cysts of enteric origin, cysts of urogenital origin, dermoid cysts and pseudocysts. [4,5] Diagnosis is extremely difficult since. The Mesenteric cyst is usually asymptomatic, but if symptomatic, abdominal pain (82%), nausea and vomiting (45%), constipation (27%) are the most common presenting symptoms. [2,3] The clinical finding of abdominal mass is encountered in more than 61% of the patients. [2,3]. As this condition is very rare and its symptomatology can resemble any other abdominal diseases, diagnosis is extremely difficult and incorrect preoperative diagnosis is often made. Hence, performing physical examination and conducting radiological investigations such as ultrasonography (USG) and computed tomography (CT) are important in making a correct diagnosis. [2,3] As well as cases of mesothelial cysts, they are typically asymptomatic but occasionally, their symptoms are vague and non-specific. [6,7] As mentioned above, imaging modalities such as USG, CT and magnetic resonance imaging (MRI) are great in identifying the character, size, location, surrounding tissues and the wall and content of the cysts. [7] Surgery is the treatment of choice, as a complete resection with negative borders is curative and often prevents recurrence. [3] We report a case of a young female patient who presented with a vague abdominal symptoms and a large cystic mass in lower abdomen. After proper evaluation, surgical exploration revealed a large simple mesothelial cyst.
