Role of CD138, CD56, and light chain immunohistochemistry in suspected and diagnosed plasma cell myeloma: A prospective study

Abstract

Introduction:Plasma cells (PCs) have conventionally been counted on the bone marrow aspirate, and small focal involvement may be missed even on bone marrow biopsy sections.Material and Methods:We aimed to study the role of CD138, CD56, anti-κ, and anti-λ immunohistochemistry (IHC) to separate PC myeloma from reactive plasmacytosis and to study the utility of these in cases suspected as myelomas and lacking >10% PCs on bone marrow aspirate. The study comprised 35 diagnosed myelomas, 20 reactive plasmacytosis, and 19 M-band positive suspected myelomas. CD138 IHC was performed on all cases along with CD56, anti-κ, and anti-λ IHC. PCs were counted on CD138-immunostained sections by manual count and by image analysis. In addition, CD56 expression was correlated with clinical features in diagnosed myeloma group.Results:In all cases, both manual counts and image analysis, PC counts were significantly higher on the CD138 stained sections than bone marrow aspirates. It was seen that the manual PC counts and image analysis counts were equivalent in diagnosed myeloma cases. CD56 expression was seen in ~62.85% diagnosed myeloma cases while it was negative in cases of reactive plasmacytosis. CD56 expression was significantly higher in patients with lytic lesions (78.26% vs. 21.74%). CD138, anti-κ, and anti-λ IHC also helped classify 11/19 (57.8%) cases correctly.Conclusion:The use of CD138 along with the light chain and CD56 IHC adds a high diagnostic value in myeloma patients and suspected myeloma cases. The PCs can be counted manually on the CD138-immunostained sections and correlate well with the counts obtained by image analysis.

Morphological and Immunohistochemical Prognostic Factors of Multiple Myeloma and their Correlation with Clinical and Laboratory Indicators of Morbidity. Summary of the Doctoral Thesis

“…In patients with a higher cellularity index in the bone marrow, MM is associated not only with a later stage of MM, according to SDC, but also with worse clinical laboratory prognostic indicators such as increased levels of B2MKB, albumin, creatinine, M-gradient, decreased platelet count and GFR. The findings of our study are consistent with those of other authors (Stifter, 2010;Bartl, 1987;Riccardi, 1990;Singhal, 2004;Dass, 2019) in that the primary diagnosis of MM can already be used to judge the prognosis of a given patient based on the cellularity of the bone marrow.…”

“…Bone marrow cellularity in MM cases is one of the most important and easily determined non-specific histological parameters (Stifter, 2010), which, according to several authors, has a prognostic significance. In patients with the highest cellularity, later stages of MM and shorter survival are more often detected (Bartl,1987, Riccardi,1990Singhal, 2004;Dass, 2019).…”

Recent updates on CAR T clinical trials for multiple myeloma

“…CD138 is a surface molecule highly expressed on MM cells [100–103]. CD138 plays a significant role in the development and/or proliferation of plasma cells.…”

Phage-Phenotype Imaging of Myeloma Plasma Cells by Phage Display

“…It is expressed on normal cell subsets, such as T, NK, B, and dendritic cells, but it is also expressed during cell activation and proliferation [11]. In addition to CD138 and CD38, other markers-namely, CD45, CD56, CD19, CD81, CD27, and CD117-are used to further distinguish between normal/reactive PCs and MM PCs during preliminary diagnosis or detection of MRD [13][14][15]. Among all, a multiparametric flow cytometry evaluation of BM from MM patients reveals two subpopulations of clonal PCs, based on the presence/absence of CD45 expression [16].…”