Diffuse Large B-cell Lymphoma Associated With Exposure to Agent Orange.

Agent Orange (AO) is a toxic herbicide carcinogen mixture of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) that was used extensively during the Vietnam conflict of the 1960s and 1970s. We present a case of an elderly veteran who presented with a progressively enlarging right neck mass. During active combat in Vietnam, he experienced extensive exposure to AO. He was eventually diagnosed with stage I diffuse large B-cell lymphoma (DLBCL) with locally advanced/bulky disease. The patient was deemed higher risk for systemic disease given the skin breakthrough at presentation. Additional labs revealed prior infection with hepatitis B with immunity. There is an association between hepatitis B virus infection and non-Hodgkin lymphoma (NHL). Large epidemiologic studies demonstrate a two times higher risk of developing DLBCL, and it is linked to worse outcomes. He commenced therapy on a rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) regimen for six cycles. He was also treated with oral entecavir prophylaxis for 18 months and continued for at least one year after his last rituximab dose.