Tissue immunomicroscopic evaluation of monoclonality of B-cell lymphomas: comparison with cell suspension studies

A series of 80 tissues removed from patients having a variety of lymphoproliferative disorders were comparatively studied by cell suspension and cryostat frozen section tissue immunomicroscopic technics. Of 39 cases of non-Hodgkin's lymphomas studied by cell suspension, only 18 had surface immunoglobulins (SIg) markers consistent with monotypia (46%). Conversely, immunohistochemistry showed 18 cases (92%). Among the 18 cases in which there was no correlation between immunohistochemistry and cell suspension studies (46%), a variety of cytologic variants of non-Hodgkin's lymphomas was recognized, including nodular poorly differentiated lymphocytic lymphoma, nodular large cell lymphoma, and a soft tissue plasmacytoma. The lack of correlation between the two technics may be due to several different mechanisms, including the selective enrichment of the suspension by nonneoplastic cell populations resulting in a sampling artifact, the disappearance of endogenous SIg in large or plasmacytoid lymphocytes, and the presence of membrane-bound exogenous polyclonal SIG. Immunohistochemistry represents a reliable, simple technic for establishing monotypia in non-Hodgkin's B-cell lymphomas.