Viral and non-viral risk factors for non-Hodgkin's lymphoma in Egypt: heterogeneity by histological and immunological subtypes.

OBJECTIVE

Non-Hodgkin's lymphomas (NHL) are etiologically heterogeneous malignancies. In Egypt, we previously reported an association of increased NHL risk with chronic hepatitis C virus (HCV) infection. Our present aim is to assess the association between HCV infection and histological subtypes of NHL.

METHODS

We conducted a case-control study at the National Cancer Institute of Cairo University. Cases with NHL (n = 486) were matched to controls (n = 786) who were orthopedic patients from the same referral regions. Participants provided a blood sample for HCV markers (anti-HCV, HCV RNA) and answered a questionnaire on possible risk factors. Case-control differences were assessed by odds ratios and 95% confidence intervals from logistic regression analysis.

RESULTS

Cases with diffuse large B cell lymphoma (n = 146), chronic lymphocytic leukemia (n = 58), marginal zone lymphoma (n = 24), follicular lymphoma (n = 23), and mantle cell lymphoma (n = 16) were recruited. HCV RNA prevalence was 27% in controls and 26%-48% in the NHL subgroups: it was associated (p < 0.001) with diffuse large B cell, marginal zone, and follicular lymphomas with odds ratios of 3.2, 4.4, and 3.3, respectively.

CONCLUSION

HCV is a risk factor for diffuse large B cell, marginal zone, and follicular lymphomas in Egypt.