Hepatitis C virus infection among cryoglobulinemic and non-cryoglobulinemic B-cell non-Hodgkin's lymphomas.
BACKGROUND AND OBJECTIVE: Since hepatitis C virus (HCV) infection has been associated with different histotypes of B-cell non-Hodgkin's lymphoma (NHL), with or without concomitant production of cryoglobulins (cryolg), we have investigated the prevalence of the infection among NHL with the aim of defining its relationship with the histotype and with the production of cryolg. METHODS: Four-hundred and seventy unselected, consecutive patients with a diagnosis of B-cell NHL were investigated. Anti-HCV antibodies (Ab) and cryolg were sought in all while HCV RNA and rheumatoid factor were detected on HCV-Ab positive samples. RESULTS: Overall, the prevalence of HCV infection was 8.9% (42/470). It was 95.4% (#21) among the 22 patients with, and 4.6% (#21) among the 448 without production of cryoIg. The most common histotype among the HCV-positive, cryoIg-producing cases, was the immunocytoma (16/21, 76%). Among the HCV-positive, non cryoIg-producing cases, the marginal zone and the follicle center lymphomas were the commonest. INTERPRETATION AND CONCLUSIONS: Close association between HCV infection and cryoIg production, already described in mixed cryoglobulinemia, is confirmed also among B-cell NHL. Nevertheless, 50% of HCV-related lymphomas are non-cryoIg producers. Low-grade lymphomas (in particular the immunocytoma) are the most frequent HCV-related lymphomas. Since new therapeutic strategies might be necessary if the virus is detected, screening for cryoIg and for HCV-Ab among B-cell NHL at diagnosis is mandatory.