Hepatitis C Virus and Risk of Lymphoma and Other Lymphoid Neoplasms: A Meta-analysis of Epidemiologic Studies

• Published in: Cancer epidemiology, biomarkers & prevention Vol. 15; no. 11; pp. 2078 - 2085
• Main Authors: Dal Maso, Luigino, Franceschi, Silvia
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA American Association for Cancer Research 01.11.2006
• Subjects: Biological and medical sciences; Case-Control Studies; Epidemiologic Studies; Hematologic and hematopoietic diseases; Hepacivirus - metabolism; Hepatitis C - complications; Hepatitis C - epidemiology; Hepatitis C virus; Hodgkin's lymphoma; Humans; Leukemias. Malignant lymphomas. Malignant reticulosis. Myelofibrosis; Lymphoma - complications; Lymphoma - diagnosis; Lymphoma - epidemiology; Lymphoma - virology; Lymphoproliferative Disorders - complications; Lymphoproliferative Disorders - diagnosis; Lymphoproliferative Disorders - epidemiology; Lymphoproliferative Disorders - virology; Medical sciences; meta-analysis; Multiple myeloma; non–Hodgkin's lymphoma; Prospective Studies; Risk; Treatment Outcome; Tumors; Hepatic disease; Malignant hemopathy; Lymphoid neoplasm; Non Hodgkin lymphoma; Epidemiology; Metaanalysis; Infection; Virus; Chronic lymphocytic leukemia; Cancerology; Lymphoproliferative syndrome; Viral disease; Risk factor; Digestive diseases; Flaviviridae; Hepatitis C virus; Hepacivirus; Public health; Viral hepatitis C
• ISSN: 1055-9965; 1538-7755
• DOI: 10.1158/1055-9965.EPI-06-0308

The present meta-analysis was conducted to evaluate the strength and the consistency of the association between hepatitis C virus (HCV) infection and non–Hodgkin lymphoma (NHL) and other lymphoid neoplasms. Only studies with ≥100 cases which were also adjusted for sex and age were included. Fifteen case-control studies and three prospective studies contributed to present analysis, nine of which had not been included in previous meta-analyses. We calculated the pooled relative risks (RR) with corresponding 95% confidence intervals (95% CI), as a weighted average of the estimated RRs by random-effect models. The pooled RR of all NHL among HCV-positive individuals was 2.5 (95% CI, 2.1-3.0), but substantial heterogeneity was found between studies and by study design. Pooled RRs were 2.5 (95% CI, 2.1-3.1) in case-control studies and 2.0 (95% CI, 1.8-2.2) in cohort ones. The strongest source of heterogeneity seemed to be the prevalence of HCV among NHL-free study subjects (RR for NHL among HCV-positive individuals 3.0 and 1.9, respectively, for ≥5% and <5% HCV prevalence). RRs were consistently increased for all major B-NHL subtypes, T-NHL, and primary sites of NHL presentation. Thus, previous suggestions that the RRs for HCV differed by NHL subtype were not confirmed in our meta-analysis. Associations weaker than with NHL were found between HCV infection and Hodgkin's lymphoma (RR, 1.5; 95% CI, 1.0-2.1) and multiple myeloma (RR, 1.6; 95% CI, 0.7-3.6), but they were based on much fewer studies than NHL. The etiologic fraction of NHL attributable to HCV varies greatly by country, and may be upward of 10% in areas where HCV prevalence is high. (Cancer Epidemiol Biomarkers Prev 2006;15(11):2078–85)