Immunohistochemical evaluation of CD20 expression in patients with multiple myeloma

Abstract

ObjectiveCD20 expression was reported at different rates in patients with multiple myeloma. The importance of this B-cell antigen for plasma cells is still unknown. This study aimed to investigate CD20 expression of myeloma cells in bone marrow, and any relationship between the stage of disease, isotype and clinical features.MethodsSixty-one patients who were admitted to the hematology clinic of the Adnan Menderes Medical School with the diagnosis of multiple myeloma according to the criteria of the “International Myeloma Working Group” were enrolled in this study. Age, gender, Durie–Salmon stage, history of autologous hematopoietic stem cell transplantation, and the distribution pattern and positivity of CD20 expression on multiple myeloma cells in bone marrow were evaluated. The Mann–Whitney U and chi-square tests were used for statistical analysis with a p-value < 0.05 being accepted as statistically significant.ResultsThirty patients (48.9%) had positive scores for CD20 with the distribution pattern being most likely interstitial in 55.6% of the cases. There was no statistically significant difference between immunohistochemical positivity for CD20 expression on multiple myeloma cells, immunoglobulin type, and the stage of disease.ConclusionThe combination of immunohistochemical studies with flow cytometry may reveal the importance of CD20 positivity in patients with multiple myeloma more clearly.

Rare Differential Diagnosis of Dyspnea: Extramedullary Plasmocytoma (EMP) of the Larynx—Case Report and Review of the Latest Literature of Laryngeal EMP and Laryngeal Involvement of Multiple Myeloma

“…Furthermore, by immunohistochemistry and fluorescence-activated cell sorting (FACS), it is possible to detect the expression of certain cell surface antigens (i.e., CD 38 and CD 138). These results help to prove the diagnosis of EMP [16].…”

A phase 1 trial of 90Y-Zevalin radioimmunotherapy with autologous stem cell transplant for multiple myeloma

“…27 In this phase 1 study, we have added 90 Y-Zevalin in MM conditioning. The rationale for targeting CD20 in MM is based on the knowledge that while CD20 is expressed in up to 49% of myeloma patients and with heterogeneous expression, 15,28,29 there is evidence that clonal CD19+/CD20+ B cells appear resistant to high dose therapy, and comprise the majority of clonal cells in myeloma patients post-ASCT. 30 Moreover, the bone marrow houses polyclonal CD20+ B cells that can be non-specific attractants for the 90 Y-Zevalin which then irradiate nearby malignant plasma cells by a crossfire effect.…”

“…There were three theoretical potential benefits to this approach all based on the known radiosensitivity of myeloma cells. There is a body of literature that would suggest that myeloma cells can express the CD20 antigen, 14,15 and myeloma stem cells have been postulated to be CD20 positive, 16 although this remains controversial. 17 Any CD20+ cells-malignant or reactive would be directly targeted by the 90 Y-Zevalin.…”

The prognostic significance of bone marrow histological evaluation in patients with multiple myeloma

“…The grade of marrow fibrosis (MF) was described on a four-point scale (MF0--MF3) based on histochemical staining for the presence of reticulin fibers [7]. The following IHC stains were evaluated: CD138, CD56, CD20, CD117, cyclin D1, p53 protein, kappa and lambda light chains to determine the clonality and to reveal the aberrant phenotype of myeloma cells (Table I) [8][9][10][11][12][13][14][15]. In this study, we use the term kappa or lambda plasma cells infiltration if the kappa positive to lambda positive cells ratio in IHC was >4:1 or <1:2 respectively.…”