Histopathological analysis of B-cell non-Hodgkin lymphomas without light chain restriction by using flow cytometry

Abstract

Detection of immunoglobulin light chain restriction (LCR) by flow cytometry (FCM) is a useful tool for B-cell non-Hodgkin lymphoma (B-NHL) diagnosis. Here, we identified B-NHLs without LCR by FCM and investigated the pathological causes for lack of LCR. A total of 89/471 cases (19%) of B-NHL were LCR-negative. The incidence of lack of LCR was 30% both in diffuse large B-cell lymphoma (DLBCL) and marginal zone lymphoma (MZL), and was 6% in follicular lymphoma (FL). In DLBCL cases, low expression of surface membrane light chain (33%), low proportion of lymphoma cells (11%), CD45 negativity (9%), and destruction or sampling error were suggested as reasons for lack of LCR. In MZL cases, the low proportion of lymphoma cells owing to admixture of many reactive germinal centres, and non-detection of plasmacytoid lymphoma cells by CD45 gating might be the reasons. Based on pathological subtypes, the frequency and reasons for lack of LCR by FCM varied.

Keywords::

• B-lymphocytes
• flow cytometry
• immunoglobulin light chain
• lymphoma
• pathology

Acknowledgements

The authors would like to thank Ms C. Kina and Ms S. Miura for their technical assistance with immunohistochemistry.

Funding

This work was supported in part by the National Cancer Center Research and Development Fund [23-A-17, 23-A-23, 26-A-4, and 26-A-24], and JSPS Grand-in-Aid for Scientific Research [C-25234567] in Japan.

Potential conflict of interest:

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