B-lymphocyte stimulator: can we consider it a marker for severity of hepatitis C virus-induced B-cell non-Hodgkin lymphoma?

Objective B-lymphocyte stimulator (BLyS) is a member of tumor necrosis factor family. BLyS is essential for the survival of normal and malignant B lymphocyte. Hepatitis C virus (HCV) infection likely represents the early event leading to BLyS upregulation. The aim of this study was to determine the relation between serum BLyS levels and the severity of HCV-related B-cell non-Hodgkin lymphoma (B-NHL). Patients and methods Seventy-eight B-NHL patients both HCV-positive and HCV-negative and 20 patients with HCV infection without lymphoproliferative disorders, in addition to 20 age-matched and sex-matched controls, were included in the study. PCR for HCV, evaluation of levels of soluble BLyS protein in blood, bone marrow aspirate and biopsy with flow cytometry, and lymph node biopsy with immunophenotyping for CD5, CD23, CD10, CD20, and cyclinD1 were performed. Results The serum BLyS levels were significantly higher in B-NHL patients and HCV patients without lymphoproliferative disorders compared with the control group. The serum BLyS levels were statistically significantly higher in aggressive lymphoma patients with HCV-positive infection compared with aggressive lymphoma patients with HCV-negative infection, but there was no statistically significant difference between BLyS levels in indolent B-NHL patients with or without HCV infections. Moreover, there was no statistically significant difference between BLyS levels in aggressive and indolent lymphoma patients with HCV-positive infection. Conclusion BLyS levels are increased in HCV-induced B-NHL but it cannot be considered as a marker for severity of the disease (indolent or aggressive). More studies are needed.