LONG BEACH, CA — A new study found no link between deployment to the Middle East during Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF) and a greater risk of developing lymphoid malignancies, but the authors cautioned that their study had important limitations.
Researchers from the VA Long Beach, CA Healthcare System, and the University of California, Irvine in Orange, CA, pointed out that U.S. military personnel deployed to the Middle East “were potentially subjected to harmful exposures, such as carcinogens from burn pits, which may increase the risk of lymphoid malignancies. Our objective was to determine the association between deployment and the risk of developing lymphoid malignancies.”
The retrospective nested matched case-control study involved a cohort of 3.5 million veterans who enlisted in the military after September 2001 and were followed until death or last follow up through September 2024. The study team identified cases of lymphoid malignancies by the VA Central Cancer Registry. Controls were randomly selected from the same base cohort, matched by year of birth, year of enlistment, sex, race and ethnicity.
The study defined exposure as deployment to the Middle East as determined by identification on the OEF/OIF roster with confirmed dates of deployment or paystubs.
The researchers reported in Cancers (Basel) that there were 1,037 cases of lymphoid malignancies and 3,572 matched controls.1
Results indicated, however, that deployment was not associated with a higher risk of developing lymphoid malignancies compared to non-deployment. “Exposure to OEF/OIF was not associated with a higher risk of developing certain types of lymphoid malignancies,” the authors wrote.
They added, “In this large, matched case-control study of U.S. veterans, deployment to the Middle East was not associated with increased risk of developing lymphoid malignancies. While these findings do not support an increased lymphoid malignancy risk, important limitations remain, including the absence of detailed exposure and potential confounding variables. Prospective monitoring of specific types and doses of exposures during military deployment, development of lymphoid and other malignancies, and their underlying pathophysiology is indicated.”
- Ma H, Gupta P. Middle East Deployment and Lymphoid Malignancies in US Veterans: A Matched Case-Control Analysis. Cancers (Basel). 2025 Sep 29;17(19):3161. doi: 10.3390/cancers17193161. PMID: 41097689; PMCID: PMC12523474.