Cryoglobulinemia and amyloidosis associated with intestinal lymphoma.

A case of lymphocytic lymphoma of the small intestine was associated with cryoglobulinemia and amyloidosis. The neoplastic lymphoid cell demonstrated surface IgG membrane markers by immunofluorescence and immunoelectron microscopy. The cryoglobulins were characterized as monoclonal IgG3 proteins with lambda light chains. Amyloidosis of the small intestine and regional lymph nodes was found in association with lymphatic infiltration of these organs, suggesting the production of amyloid in situ.