A Common Clonal Origin of Nodal Marginal Zone B-Cell Lymphoma and Plasma Cell Myeloma Demonstrating Different Immunophenotypes

Abstract

We demonstrated an 83-year-old male case of composite lymphoma. Before 18 years, he was diagnosed with nodal marginal zone B-cell lymphoma in the cervical lymph node. Peripheral blood showed anemia and IgA (kappa)-type monoclonal gammopathy (IgA; 3,625 mg/dL). Bone marrow aspiration biopsy exhibited plasma cell myeloma, in which atypical plasma cells were positive for cytoplasmic IgA (kappa) and atypical lymphoid cells intermingled were positive for CD20. In contrast, cervical lymph node biopsy revealed nodal marginal zone B-cell lymphoma, in which lymphoma cells were positive for cytoplasmic IgG (lambda). Southern blotting analysis of the IgH gene showed same clonal rearrangement band in both lymph node and bone marrow samples and additional band in the bone marrow. Sequence analyses of the IgH gene showed an identical sequence of CDR3 in both samples. Thus, we demonstrated a common clonal origin of composite lymphoma comprising nodal marginal zone B-cell lymphoma and plasma cell myeloma. Nodal marginal zone B-cell lymphoma recurred in cervical lymph node and involved into the bone marrow, differentiating into plasma cell myeloma in which Ig isotype switched and monoclonal gammopathy developed. Sequence analysis of the IgH gene was a powerful tool for determination of clonal origin.

Practical diagnostic approaches to composite plasma cell neoplasm and low grade B‐cell lymphoma/clonal infiltrates in the bone marrow

“…Low grade B‐cell non‐Hodgkin lymphoma coexisting with clonally unrelated PCN is uncommon and has been reported in the past as case reports and series . Although uncommon, it should be part of the differential diagnosis when faced with B‐NHL exhibiting PD or a PCN with lymphoplasmacytic morphology .…”

Multiple cutaneous monoclonal B‐cell proliferations as harbingers of systemic angioimmunoblastic T‐cell lymphoma

“…Multiple histologically and immunologenetically distinct B‐cell neoplasms developing in one patient is not particularly uncommon 39–55 . Many patients with low‐grade B‐cell lymphomas such as follicular lymphoma, chronic lymphocytic leukemia/small lymphocytic lymphoma and externodal marginal zone lymphoma will develop histological progression to DLBCL.…”

Immunophenotyping of selected hematologic disorders – focus on lymphoproliferative disorders with more than one malignant cell population

“…In most cases studied by molecular methods, two separate clonal populations were found . However, in rare patients, a common clonal origin was suggested .…”

“…Several case reports of biclonal or composite B‐cell lymphomas have been published . The reported overall incidence of B‐cell chronic LPDs presenting with more than one aberrant population in one larger series ( n = 477) studied by FCM was approximately 5% .…”