Treatment and survival of U.S. Vietnam Veterans with concurrent lymphoid malignancies

Abstract: INTRODUCTION: In Vietnam veterans, exposure to military toxicants, such as Agent Orange, may be associated with lymphoid malignancies. Toxicant exposure may increase the likelihood of being diagnosed with concurrent lymphoid malignancies, which can occur as composite, discordant, or transformed lymphomas. MATERIALS AND METHODS: We conducted a large, retrospective case-control study using the national VA Central Cancer Registry to identify cases of concurrent lymphoid malignancies compared to controls of single lymphoid malignancies and the association with Agent Orange. RESULTS: The occurrence of concurrent lymphoid malignancies was rare (n = 128/32,889, 0.4%). The most common concurrent lymphoid malignancy combinations were chronic lymphocytic leukemia (CLL) and diffuse large B-cell lymphoma, CLL and plasma cell neoplasms, CLL and marginal zone lymphoma, and diffuse large B-cell lymphoma and follicular lymphoma. Agent Orange exposure was not associated with increased odds of being diagnosed with concurrent lymphoid malignancies. Though limited in sample size, patients with concurrent lymphoid malignancies did not appear to have a worse survival compared to patients with single lymphoid malignancies. In our qualitative analysis of treatments for those with concurrent diagnoses, veterans primarily underwent first-line treatment for the more aggressive diagnosis, with few requiring treatments for both diagnoses during their clinical course. CONCLUSIONS: In this Vietnam Era cohort, Agent Orange exposure did not appear to influence the development of concurrent lymphoid malignancies. Having a diagnosis of concurrent lymphoid malignancies did not appear to significantly affect patient survival. This will inform counseling of veterans with Agent Orange exposure and has implications for future policy development.