Appearance of lymphomatous involvement of the mesentery by ultrasonography and body computed tomography: the "sandwich sign".

A characteristic appearance of lymphomatous involvement of the mesentery is demonstrated by ultrasonography and computed tomography. The presence of a lobulated confluent mass infiltrating the mesenteric leaves and encasing the superior mesenteric artery and veins producing a "sandwich-like" appearance is reported in seven patients with Hodgkin and non-Hodgkin lymphoma. Retroperitoneal adenopathy was present in all seven patients. In six, a correct prospective diagnosis was made and a major revision of therapeutic planning occurred. Laparotomy was deferred in three patients. The anatomy, pathophysiology, and clinical importance are detailed.