Immunoglobulin-containing intranuclear inclusions in plasma cells in a case of IgG myeloma

Follicular lymphoma with prominent Dutcher body formation: a pathologic study of 3 cases in comparison with nodal or splenic lymphoplasmacytic lymphoma and marginal zone lymphoma

Dutcher bodies have been described in lymphoid neoplasms with plasmacytic differentiation, including plasma cell myeloma, lymphoplasmacytic lymphoma, and marginal zone lymphoma. We report a pathologic study of 3 cases of follicular lymphoma with extensive Dutcher body formation in comparison with lymphoplasmacytic lymphoma and marginal zone lymphoma. Of 3 cases, 1 showed a follicular growth pattern, whereas the other 2 cases demonstrated only a vague nodular appearance highlighted by immunohistochemical analysis. Cells containing Dutcher bodies were counted at 25, 90, or 110 per high-power field in each case, respectively. In 2 cases, cells with Dutcher bodies were clustered in an intrafollicular distribution, a possible histopathologic clue for follicular lymphoma. Immunoglobulin M κ was identified as the component of Dutcher bodies in all 3 cases, implying a possible molecular basis for the formation of Dutcher bodies in B-cell lymphomas. All 3 cases had cytogenetic changes supporting the diagnosis of follicular lymphoma, including dual rearrangement of BCL2 and BCL6, rearrangement of BCL2 with trisomy 3 (BCL6), and isolated BCL6 rearrangement. We emphasize immunohistochemical analyses with anti-κ/λ and anti-immunoglobulin heavy-chain isotypes to characterize Dutcher bodies and document clonality in addition to the routine lymphoma workup and indicated cytogenetic studies in B-cell lymphomas with prominent Dutcher bodies.

A study of Russell bodies in human monoclonal plasma cells by means of immunofluorescence and electron microscopy

Five patients with a serum M component were shown to possess plasma cells containing Russell bodies. Four of the patients suffered from multiple myeloma, whereas the fifth probably had a different disease or was in a premyeloma stage. The Russell bodies stained blue with the May-Grünwald-Giemsa stain and were found both in the nuclei and in the cytoplasm of the plasma cells. Ultrastructural studies showed that the Russell bodies were osmophilic and those located in the cytoplasm were always situated within the cisternae of the rough endoplasmic reticulum. The intranuclear Russell bodies were always surrounded by a triple layered membrane, and some evidence was obtained that these bodies were first formed within the perinuclear space of the cells. Immunofluorescence studies using anti-L chain conjugates showed a positive marginate straining of the intranuclear as well as the cytoplasmic Russell bodies of the cells from all patients. Only one patient had cells with Russell bodies which also stained their location in the plasma cells. It is concluded that some plasma cells in multiple myeloma may produce an excessive amount of L chains which, in combination with a failure in the secretion of immunoglobulin molecules, may lead to the formation of Russell bodies.