This 77 year-old female with known chronic lymphocytic leukaemia presented in extremis with abdominal pain, abdominal distention, acidosis and elevated lactate. A CT was performed for possible ischaemic colitis.

There is caecal pneumatosis and dilatation consistent with ischaemia (green arrows, click image). There is also a mesenteric and paraaortic nodal mass with the “hamburger sign” (red arrows) suggesting lymphoma.

Americans may try to tell you this is the sandwich sign. The sign is specific for mesenteric lymphoma (typically non-Hodgkin’s) unless the patient has had a transplant. In this case posttransplant lymphoproliferative disorder should be considered.

Reference: Hardy SM. The Sandwich Sign. Radiology 2003; 226:651–652

Credit: Dr Laughlin Dawes