Extranodal Marginal Zone Lymphoma of the Breast in a Patient with Chronic Hepatitis C Infection: A Case Report.

Primary breast lymphomas account for less than 1% of all non-Hodgkin lymphomas and 0.04-0.5% of all malignant breast neoplasms. We report a case of breast extranodal marginal zone lymphoma (EMZL) in a 60-year-old woman with chronic hepatitis C virus (HCV) infection. After comprehensive evaluation excluded other known etiologies, chronic HCV infection emerged as the most plausible contributing factor. Epidemiologic and biological evidence supports an association between HCV and B-cell non-Hodgkin lymphomas, particularly marginal zone lymphomas. Our case adds to the limited literature suggesting that HCV should be considered as a potential etiological factor in breast EMZL. We discuss the emerging role of direct-acting antiviral (DAA) therapy in HCV-associated indolent lymphomas and its implications for management.