The chemokine receptor CXCR4 has been implicated in the migration and trafficking of malignant B cells in several haematological malignancies. Over‐expression of CXCR4 has been identified in haematological tumours, but data concerning the role of this receptor in diffuse large B cell lymphoma (DLBCL) are lacking. CXCR4 is a marker of poor prognosis in various neoplasms, correlating with metastatic disease and decreased survival of patients. We studied CXCR4 involvement in cell migration in vitro and dissemination in vivo. We also evaluated the prognostic significance of CXCR4 in 94 biopsies of DLBCL patients. We observed that the level of expression of CXCR4 in DLBCL cell lines correlated positively with in vitro migration. Expression of the receptor was also associated with increased engraftment and dissemination, and decreased survival time in NOD/SCID mice. Furthermore, administration of a specific CXCR4 antagonist, AMD3100, decreased dissemination of DLBCL cells in a xenograft mouse model. In addition, we found that CXCR4 expression is an independent prognostic factor for shorter overall survival and progression‐free survival in DLBCL patients. These results show that CXCR4 mediates dissemination of DLBCL cells and define for the first time its value as an independent prognostic marker in DLBCL patients. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd

True histiocytic lymphoma is considered a rare entity, and its diagnosis requires the concordance of morphological, immunophenotypic, and molecular findings. The association of malignant lymphoma with tumors in the monocyte-macrophage system has rarely been described. We present a case of mucosa-associated lymphoid tissue (MALT)-type low-grade B-cell lymphoma of the stomach, contiguous to a large tumoral mass that fulfills the morphological criteria (large cells with abundant pale cytoplasm and lobulated or kidney-shaped nuclei) and immunophenotypical features (human leukocyte antigen-DR locus, CD68, S-100, lysozyme immunoreactivity, and negative B- and T-cell markers) required for the diagnosis of histiocytic lymphoma. The patient remains in complete remission 18 months after surgery. The association of low grade-malignant lymphoma with tumors of monocyte-macrophage system cells is an exceedingly rare phenomenon. Whether these tumors are directly related or occur due to pure chance requires the identification of new cases and further study.

patients with CLL. BCMA expression was significantly higher on CLL cells than on normal B cells. BCR and CD40+IL4R stimulation promoted an increase in TACI and BCMA expression, cell viability and activation in normal B cells. A similar effect was observed in CLL cells after CD40+IL4R but not BCR stimulation. BCMA expression correlated with unmutated IGHV genes, poor-risk cytogenetics, and short progression-free survival. These findings further characterize the link between CD40+IL4R regulatory signals, BAFF, APRIL and their receptors and the survival of leukaemic cells and clinical features of CLL.

Background The diagnosis of CLL is supported by a typical morphology and immunophenotype and usually does not present difficulties. Nevertheless, some patients with CLL can show an atypical phenotype, this raising the possibility of a lymphoproliferative disorder other than CLL. It has been recently shown that the expression of CD200 could be a rather consistent marker for CLL. Methods The expression of CD200 was investigated in 120 consecutive patients with B‐cell chronic lymphoproliferative disorders (B‐CLPD) (65 cases diagnosed as typical CLL, 16 atypical CLL, and 39 non‐CLL before entering the study) by using multiparametric flow cytometry with four color combinations. CD200 was analyzed as percentage of positive cells (≥30%) and MFIR expression. ROC curves were used to determine the cut‐off for the CD200 MFIR. Matutes score (MS) was used as comparator. Results All 81 (100%) patients classified as CLL and 25 of 39 (64.1%) classified as non‐CLL expressed high CD200 expression (≥30%). CD200 expression showed a high sensitivity (100%) and a low specificity (35.9%), and the accuracy was similar to that of Matutes score markers (range: 79.2%–86.7%); except SmIg that was 59.1%. The addition of CD200 to the Matutes score correctly identified 74 of 81 (91.4%) CLL cases including 9 of 16 atypical CLL cases. As per non CLL cases, 37 of 39 (94.9%) were correctly diagnosed by the modified system. Altogether, CD200 improved the diagnostic accuracy of Matutes score from 86.7% to 92.5% (P < .01). Conclusion These results show that CD200 is a valuable, albeit not specific, CLL diagnostic marker. © 2018 International Clinical Cytometry Society