Risk of non-Hodgkin's lymphoma in patients with hepatitis C virus infection

Hepatitis C virus (HCV) has been suggested to play an etiological role in t he development of B-cell non-Hodgkin's lymphoma (NHL) in Italy. However, an other study in Scotland questioned increased risk of development of NHL in patients with chronic HCV infection. A total of 2,162 patients admitted to 3 hospitals in Osaka, where the incidence of HCV-related hepatitis is highe st in Japan, during the period from 1957 to 1997 were followed up from the date of diagnosis of chronic HCV-related hepatitis until 30 October 1997, O verall, 12,404.5 person-years of observation were accrued with a follow-up period ranging from 0.25 to 40.4 (average 5.74) years. NHL of the B-cell ty pe developed in 4 patients. The interval between onset of chronic HCV and N HL ranged from 6 to 36 (median 13) years. Expected number of cases of NHL i n the sex-, age- and calender year-matched general population was 1.90, whi ch gave a relative risk (RR) of 2.10 (95% confidence interval 0.57-5.38; p = 0.247). Taking the much higher RR for hepatocellular carcinoma among pati ents with HCV infection into account, chronic HCV infection was considered to be moderately associated with increased risk of NHL, (C) 1999 Wiley-Liss , Inc.