Dental X-Rays Linked to Common Brain Tumor Say Researchers

Posted on April 26, 2012

Meningioma, the most common primary brain tumor in the United States, accounts for about 33% of all primary brain tumors. The most consistently identified environmental risk factor for meningioma is exposure to ionizing radiation. In the largest study of its kind, researchers from Brigham and Women's Hospital (BWH), Yale University School of Medicine, Duke University, UCSF and Baylor College of Medicine have found a correlation between past frequent dental x-rays and an increased risk of developing meningioma.

Elizabeth Claus, MD, PhD, a neurosurgeon at BWH and Yale University School of Medicine at New Haven, says, "The findings suggest that dental x-rays obtained in the past at increased frequently and at a young age, may be associated with increased risk of developing this common type of brain tumor. This research suggests that although dental x-rays are an important tool in maintaining good oral health, efforts to moderate exposure to this form of imaging may be of benefit to some patients."

Claus and her colleagues studied data from 1,433 patients diagnosed with meningioma between 20 and 79 years of age between May 2006 and April 2011 and compared the information to a control group of 1350 participants with similar characteristics. They found that patients with meningioma were twice as likely to report having a specific type of dental x-ray called a bitewing exam, and that those who reported having them yearly or more frequently were 1.4 to 1.9 times as likely to develop a meningioma when compared to the control group. There was an even greater increased risk of meningioma in patients who reported having a panorex x-ray exam. Patients who reported having this exam taken under the age of 10, were 4.9 times more likely to develop a meningioma compared to controls. Those who reported having the exam yearly or more frequently than once a year were nearly 3 times as likely to develop meningioma when compared to the control group.

The amount of radiation given in dental x-rays is lower than it was two decades ago, but it is still radiation.

Cancer.org reports that Otis W. Brawley, M.D., chief medical officer of the American Cancer Society, said, "We need more data before we can even begin to state there is a relationship between dental x-rays and these tumors. Until that research is done, the best advice we can give people is to get dental x-rays when they are necessary and only when they are necessary. The dose of radiation given in a bitewing or panoramic x-ray is lower today than it was two decades ago. Nonetheless, x-rays should be done only when necessary. This is true of all x-ray technology, and it's the same advice experts would have given without this study."

These findings are published in the April 10, 2012 issue of Cancer.