Research has established a significant connection between exposure to Agent Orange, a defoliant used during the Vietnam War, and an increased risk of developing a rare form of bone marrow cancer known as myelodysplastic syndrome (MDS). The findings were presented at the American Society of Hematology conference held in Orlando on December 11, 2023.
The study, led by Dr. Mikkael Sekeres, chief of hematology at the University of Miami’s Sylvester Comprehensive Cancer Center, highlights that individuals exposed to Agent Orange are more likely to be diagnosed with MDS at an earlier age and may experience a more aggressive form of the disease. Approximately 2.6 million U.S. service members could have encountered this toxic chemical during their military service.
Agent Orange contains a highly toxic form of dioxin, which has been previously linked to several blood cancers, including lymphoma, multiple myeloma, and leukemia. Until now, a direct correlation with MDS had not been clearly established due to a lack of comprehensive data. Dr. Sekeres noted, “No one studied this before because there haven’t been organized registries with the data needed to make this connection.”
Study Insights and Implications
The research team analyzed data from a federally funded study that enrolled patients suspected of having or diagnosed with MDS between 2016 and 2024. Out of the 2,115 participants, 130 reported exposure to Agent Orange. The results indicated that those exposed to the defoliant tended to develop MDS at younger ages and had a higher incidence of harmful genetic mutations associated with the condition.
Dr. Sekeres explained that MDS is characterized by a gradual accumulation of genetic damage over time. “MDS isn’t a one-hit wonder,” he said. “Patients have one genetic mutation that occurs, then another, then another. It takes decades for those mutations to develop, and with an exposure like Agent Orange, patients can acquire that first mutation at a younger age than they normally would.”
The study also revealed that patients exposed to Agent Orange had a doubled risk of disease progression following diagnosis. Interestingly, while the progression of MDS was more pronounced, the overall survival rates for these patients were similar to those who were not exposed to the defoliant.
Disparities Among Veterans
The research further identified disparities in exposure rates among different demographic groups. Black veterans were found to be more than twice as likely to have been exposed to Agent Orange compared to their white counterparts, despite representing only 16% of the male service members who served in Vietnam. “This toxin may have hit a particularly vulnerable population,” Dr. Sekeres remarked.
These findings could have significant implications for veterans seeking medical treatment for MDS. The research team aims to validate their results using national veteran databases, which could potentially facilitate coverage for treatment among those who were exposed to Agent Orange. Dr. Sekeres expressed hope for the veterans, stating, “Veterans have been waiting a long time for someone to take this seriously. If our work can move the needle even a little, that feels incredibly meaningful.”
It’s important to note that findings presented at medical conferences should be considered preliminary until they are published in a peer-reviewed journal. For more information on myelodysplastic syndrome, the American Cancer Society offers additional resources.
