Monoclonal gammopathies associated with lymphoproliferative disorders: a morphologic study.

Abstract

In 15 patients with lymphoproliferative diseases of various types, histologic studies suggested monoclonal gammopathy. This was confirmed immunoelectrophoretically in the serum, urine, or both, from 10 patients. Seven of these 10 patients had IgM (kappa), one had IgM (lambda), one had IgA (kappa), and one had Bence Jones (lambda). Of the other five patients, three had polyclonal IgM elevations and two had no detectable monoclonal or polyclonal immunoglobulin abnormalities. Nuclear periodic acid-Schiff positive globules, heretofore considered to be characteristic of macroglobulinemia of Waldenstrom, were found in only three patients with IgM monoclonal gammopathy. In two of these, the globules were found only after a prolonged search. They were also seen in one patient with IgA monoclonal gammopathy. They were abundant in one of three patients with polyclonal IgM gammopathy. A high frequency of nuclear PAS positive globules was also observed in three additional patients. One of these patients had an unclassifiable malignant lymphoma involving a submandibular lymph node, and the other two had lymphoid hyperplasias involving the skin and nasopharynx, respectively. Nuclear periodic acid-Schiff positive globules were more abundant and more consistently present in our cases of polyclonal IgM gammopathy than in cases with monoclonal IgM gammopathy, regardless of the neoplastic or non-neoplastic nature of the immunoglobulin-producing lesions.