With the advent of ultrasonography and computed tomography in the diagnosis of nodal and/or extranodal manifestation of non-Hodgkin's lymphoma (NHL) lymphomatous involvement of sites other than lymph nodes is seen with increasing frequency. - Review of patients with newly diagnosed or recurrent disease revealed 93 unusual extranodal sites below the diaphragm in peritoneal or retroperitoneal structures or organs. - Concomitant retroperitoneal and/or mesenteric adenopathy was common; extranodal involvement was rarely the only site of initial or recurrent lymphoma.