Characteristics of CD5-Positive Splenic Marginal Zone Lymphoma with Leukemic Manifestation ; Clinical, Flow Cytometry, and Histopathological Findings of 11 Cases

Abstract

Splenic marginal zone lymphoma (SP-MZL) is a rare low-grade B-cell neoplasm that often shows leukemic manifestation. Less than 20% of cases of SP-MZL express CD5. We analyzed 11 cases of CD5-positive SP-MZL with leukemic manifestation. The clinical characteristics of these cases did not differ from those of CD5-negative SP-MZL. Flow cytometry revealed positive results as follows : CD3, 0/9 ; CD5, 11/11 ; CD10, 0/11 ; CD11c, 4/10, CD13, 5/11 ; CD19, 11/11 ; CD20, 10/11 ; CD21, 4/4 ; CD22, 7/7 ; CD23, 5/10 ; CD25, 8/11 ; FMC7, 5/7 ; κ type 6/9, and λ type 2/9. All 3 cases with monoclonal γ-globulinemia expressed CD13. Resected spleen exhibited a proliferation of neoplastic cells in white pulp in all 8 splenectomy patients and a marginal pattern was detected in 5 patients. Only 2 cases showed involvement of red pulp. Immunohistochemistry showed that the lymphoma cells were positive for CD5, CD20, and BCL-2 and negative for CD3, CD10, cyclin D1, BCL-6, and MUM-1 in all 11 cases. These results suggest that CD5-positive SP-MZL differs from B-cell chronic lymphocytic leukemia, that CD13 expression is found in about half of CD5-positive SP-MZL cases, and that CD5-positive SP-MZL may be related to memory B-cell neoplasm or plasma cell differentiation.

Immunoarchitectural patterns in splenic marginal zone lymphoma: correlations with chromosomal aberrations, IGHV mutations, and survival. A study of 76 cases

“…Importantly, molecular and cytogenetic findings could help to refine the diagnosis in difficult cases. As previously reported by our group and others, 19,35 CD5 can be expressed in SMZL without clinicopathological, biological or cytogenetic specificity, with the exception of a higher lymphocyte count at the time of diagnosis. Mantle cell lymphoma can be easily eliminated by the absence of cyclin D1 expression and massive macronodular infiltration by small irregular cells.…”

Tissue flow cytometry immunophenotyping in the diagnosis and classification of non‐Hodgkin's lymphomas: A retrospective evaluation of 1,792 cases

“…The surface or cytoplasmic light-chain evaluation was the most useful parameter in identifying a B-cell lymphoma, whereas CD5 and CD10 are useful in identifying the different subtypes (1). However, their specificity is not absolute on neoplastic cells, as stands out from data also reported by us in Table 4; in fact they may be absent in FL (CD10 À FL) (37) or can be unexpectedly expressed elsewhere, such as CD5 on some SMZL cases (5,49) and FL (36,39,50,51), CD10 on SLL (50,51), NMZL (43), MCL and MALT (37), and HCL (52), CD5/ CD10 coexpression on DLBCL (35,50,53). These kinds of B-NHL still remain challenging for flow cytometrists, because the lack of a specific phenotype and their great heterogeneity, especially observed among MZL (nodal, splenic, extranodal), SL and LPL, determine their identification mainly on the j/k ratio.…”

Differential diagnosis of chronic lymphocytic leukemia/small lymphocytic lymphoma and other indolent lymphomas, including mantle cell lymphoma

“…Kojima M et al 12 reported 11 patients with CD5-positive splenic MZL with leukemic manifestation. They found that less than 20% of splenic MZL patients are CD5 positive.…”