Consistent pattern of increased risks of acoustic neuromas and brain tumors


April 5... Taken together, the available epidemiological studies of long-term cell phone users point to a "consistent pattern" of increased risks of acoustic neuromas and brain tumors, according to a new analysis by the Hardell-Mild team in Sweden.

In their
paper, which was posted on the Occupational and Environmental Medicine Web site yesterday, Lennart Hardell of Örebro University and Kjell Hansson Mild of the National Institute for Working Life in Umeå show that the tumor risk among those who have used mobile phones for ten years or more is highest on the same side of the head the phone was used (ipsilateral exposure). "These results are certainly of biological relevance since the highest risk was found for tumors in the most exposed area of the brain using a latency period that is relevant in carcinogenesis," they wrote, adding that, "Our findings stress the importance of longer follow-up to evaluate long-term health risks from mobile phone use."

The Swedish researchers and their American collaborator, Lloyd Morgan of Berkeley, CA, assembled a total of 15 case-control epidemiological studies, of which 11 had data for those who had used cell phones for ten or more years. In their meta-analysis, they found that the long-term, ipsilateral risk was two-and-a-half times higher for acoustic neuromas and twice as high for glioma (a type of brain tumor) as would normally be expected. Both risk estimates are statistically significant.

Earlier this year, a
meta-analysis by members of the Interphone study group also reported an increased risk of ipsilateral brain tumors among those who had used mobile phones for ten or more years (see our January 22 post). Previously, Interphone researchers had found an elevated risk of acoustic neuromas among long-term users. See also our comment "Is There a Ten-Year Latency for Cell Phone Tumor Development?"