Monoclonal gammopathy (IgM-k) in a patient with Burkitt's type lymphoblastic lymphoma.

We report a Burkitt's type lymphoblastic lymphoma (B-LL) case characterized by an abnormal IgMk immunoglobulin secretion and referred to us on February 12, 1982. The diagnosis has been histologically documented and the pathological stage of the disease (IV B) was determined according to the diagnostic criteria usually employed for the non-Hodgkin's lymphoma (NHL). Serum proteins were determined by electrophoresis and immunodiffusion. The review of the literature has allowed us to ascertain that the presence of a monoclonal IgM peak can be associated with NHL, particularly with those of B cell type and in adult subjects. Up to now, only six IgM B-LL secreting cases have been described. The biological and prognostic significance of this elevated Ig secretion is uncertain; therefore it may be important for the future to evaluate, in B-LL this immunological parameter.