IgG monoclonal gammopathy associated with lymphoproliferative disorders.

The association of IgG monoclonal gammopathy with lymphocytic lymphoma and chronic lymphocytic leukaemia is reported. Although rare, such immunoglobulin synthesis may have prognostic importance and is of value in monitoring the effect of therapy. The morphological features which should draw attention to this pattern of protein abnormality are briefly reviewed. This finding emphasises the histogenesis of these tumours from the immune system and questions their classification on a purely morphological basis.