Hepatitis Virus-associated Non-hodgkin Lymphoma: Pathogenesis and Treatment Strategies.

Over the last decade, epidemiological studies have discovered a link between hepatitis C virus (HCV) and hepatitis B virus (HBV) infection and non-Hodgkin lymphoma (NHL). The regression of HCV-associated NHL after HCV eradication is the most compelling proof supporting HCV infection's role in lymphoproliferative diseases. HBV infection was found to significantly enhance the incidence of NHL, according to the epidemiological data. The exact mechanism of HCV leading to NHL has not been fully clarified, and there are mainly the following possible mechanisms: (1) Indirect mechanisms: stimulation of B lymphocytes by extracellular HCV and cytokines; (2) Direct mechanisms: oncogenic effects mediated by intracellular HCV proteins; (3) hit-and-run mechanism: permanent genetic B lymphocytes damage by the transitional entry of HCV. The specific role of HBV in the occurrence of NHL is still unclear, and the research on its mechanism is less extensively explored than HCV, and there are mainly the following possible mechanisms: (1) Indirect mechanisms: stimulation of B lymphocytes by extracellular HBV; (2) Direct mechanisms: oncogenic effects mediated by intracellular HBV DNA. In fact, it is reasonable to consider direct-acting antivirals (DAAs) as first-line therapy for indolent HCV-associated B-NHL patients who do not require immediate chemotherapy. Chemotherapy for NHL is affected by HBV infection and replication. At the same time, chemotherapy can also activate HBV replication. Following recent guidelines, all patients with HBsAg positive/HBV DNA≥2,000 IU/mL should be treated for HBV. The data on epidemiology, interventional studies, and molecular mechanisms of HCV and HBV-associated B-NHL are systematically summarized in this review.