Association between hepatitis C virus and non-Hodgkin's lymphoma, and effects of viral infection on histologic subtype and clinical course

PURPOSE: Because an etiologic role for hepatitis C virus in non-Hodgkin's B -cell lymphoma has been suggested by several reports, we assessed the preva lence of hepatitis C virus infection in patients with non-Hodgkin's B lymph oma and in controls, and evaluated the influence of viral infection on hist ologic and clinical features of the lymphoma patients. PATIENTS AND METHODS: We prospectively investigated 175 consecutive patient s with non-Hodgkin's lymphoma and 350 controls for serologic and molecular markers of hepatitis C virus infection. Controls were selected from inpatie nts (n = 175) and outpatients (n = 175) cared for at our hospital. Patients with lymphoma who had hepatitis C virus infection were tested for mixed cr yoglobulinemia. Aminotransferase levels were measured in all lymphoma patie nts at baseline and during and after chemotherapy. RESULTS: Hepatitis C virus prevalence in patients with non-Hodgkin's lympho ma was significantly greater than in control subjects (37% vs 9%, P = 0.000 1). Among patients with lymphoma, viral infection was associated with older mean (+/-standard deviation) age (67 +/- 14 vs 61 +/- 8 years, P = 0.001), and women (41 of 87, 47%) were more likely than men (24 of 88, 27%) to hav e evidence of hepatitis C infection (P = 0.006). Thirteen of the 20 cases o f immunocytoma were associated with hepatitis C virus infection, which was also more common in patients with orbital and conjunctival localization of lymphoma. Patients with mucosa-associated lymphoid tissue (MALT) lymphoma o f the stomach were less likely to have evidence of hepatitis C infection. M ixed cryoglobulinemia was much more common in patients with hepatitis C vir us infection (14 of 65 vs 1 of 110, P = 0.0001); it was not associated with the histologic type of lymphoma. Patients with and without hepatitis C vir us infection underwent similar chemotherapy regimens and had no differences in response to chemotherapy or in overall and disease-free survival. Hepat ic toxicity from chemotherapy was seen only in patients with hepatitis C vi rus infection, although all but one of these patients were able to complete their planned treatment. CONCLUSION: These findings suggest that the hepatitis C virus may have a ro le as an etiologic agent in non-Hodgkin's B-cell lymphoma. Some clinical an d pathologic features of the disease are associated with hepatitis C virus infection, but the virus does not seem to affect prognosis. (C) 1999 by Exc erpta Medica, Inc.