Chylous mesenteric cysts: a rare surgical challenge.

A mesenteric cyst is defined as a cyst that is located in the mesentery of the gastrointestinal tract and may extend from the base of the mesentery into the retroperitoneum. It is often asymptomatic and therefore it is usually found as an incidental finding. Preoperative diagnosis may be possible with computed tomography and magnetic resonance imaging. However, the correct diagnosis can only be made with histology. The first-choice therapy is the complete removal of the cyst, which must be accurately planned according to the anatomy of the lesion, its dimensions and its relationships with major abdominal structures. We present two clinical cases: the one of a 30-year-old man with a mesenteric cyst that was removed by laparoscopy and the other of a 61-year-old woman who underwent open excision of a huge retroperitoneal cyst.