An association between hepatitis C virus (HCV) infection and B-cell non-Hodgkin lymphoma has been reported from several countries. The data from Zuckerman and colleagues suggest that this association also occurs in the United States [1].

We retrospectively reviewed 312 patients with non-Hodgkin lymphoma at City of Hope National Medical Center (in suburban Los Angeles) in whom HCV serologic studies were done for screening and during follow-up after therapy between February 1992 and December 1995 [2]. Thirty-six of these 312 patients (11.5% [95% CI, 8.2% to 15.6%]) were positive for HCV antibody. Twelve patients were female, and 24 were male. Twenty-two patients (7% [CI, 4.5% to 10.5%]) were HCV positive before receiving any transfusions. These figures are higher than those reported in healthy U.S. blood donors (0.4%) but not as high as in the Los Angeles County-University of Southern California Medical Center study sample [3].

There is a known association between HCV positivity and level of education, low socioeconomic status, sex, and ethnicity [3, 4]. The total black and Hispanic patient population at City of Hope National Medical Center is approximately 25%, much lower than that at Los Angeles County-University of Southern California Medical Center. This difference in patient demographic characteristics may explain the lower prevalence of HCV in our population despite the geographic proximity of the two institutions.

The City of Hope data support the conclusion that the prevalence of HCV positivity in patients with non-Hodgkin lymphoma is still much higher than expected, even after adjustment for differences in patient demographic characteristics. We agree that this association merits further prospective investigation. Perhaps HCV testing should be part of the evaluation of all patients with non-Hodgkin lymphoma because its presence can have important therapeutic implications.