Veterans of the Global War on Terror who have suffered moderate-to-severe or penetrating traumatic brain injuries are at a significantly increased risk of developing brain cancer, according to a study published Thursday to the Journal of the American Medical Association’s open network.
Moderate or severe TBI showed a 90% increased risk for brain cancer, and those with penetrating TBI had a threefold risk, researchers from the Uniformed Services University of Health Sciences found.
“Traumatic brain injury is not only common in the military, but also in the general population as well,” Air Force Col. (Dr.) Ian Stewart, study author and professor at USU, said in a release. “While these results may not be generalizable to the population at large, given that military cohorts are different from the general population in many ways, it is possible that more severe TBI increases risk in the civilian population as well.”
The study examined the medical records of nearly 2 million veterans from 2004 to 2019, finding that while concussions ― also known as mild TBI― were not associated with an increased risk of brain cancer, more serious head injuries were.
RELATED
About 450,000 individuals from the group had experienced mild TBI, while 47,000 were diagnosed with moderate-to-severe injuries. Another 17,000 had fully penetrating TBIs, which is the term for an impact that fractures the skull — including bullet wounds.
Out of 2 million veterans, 0.02% of the group with no TBI or mild TBI developed brain cancer. Of those who endured moderate or severe TBI, 0.04% developed brain cancer. Brain cancer diagnoses were found in 0.06% of veterans who suffered an incident of penetrating TBI.
“While the absolute number of brain cancer diagnoses was small, these diagnoses are associated with profoundly poor outcomes,” according to the study.
There has long been a suspected link between head injuries and brain cancer. As far back as 1978, a study in rats found that those who had been inflicted with a penetrating TBI ― via stab wound ― were more likely to develop brain cancer later on, possibly because of inflammation and other changes to the brain as a consequence of the trauma.
A more recent study of brain cancer cells found that they showed signs of “inflammatory wound response.”
“Given that TBI is a common injury incurred in the course of military service, further research of this rare but devastating condition is needed to better identify those at risk and develop screening protocols.”
Meghann Myers is the Pentagon bureau chief at Military Times. She covers operations, policy, personnel, leadership and other issues affecting service members.