Objective: The hypothesis that "cell phone induces brain tumor" has become a target of much controversy for several decades and is still a matter of debate even now. We aim to make a systematic review and meta-analysis based on published studies on glioma to identify current evidences for evaluating mobile phones and glioma risk, especially on long-term use of mobile phones.
Methods: The study was conducted according to the Cochrane systematic review methods and reported according to the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) statement according to a prospective research protocol accessed via http://www.crd.york.ac.uk/prospero. The software RevMan 5 was used for statistic analysis. Latency and lateralization were used for the examining the dose-response relationship.
Results: Overall evidence suggested the increased risk of glioma among long-term ipsilateral users of mobile phone with an odds ratio (OR) of 1.46[1.12, 1.92] based on meta-analysis. Especially, for low-grade glioma, long-term use yielded an OR value of 2.27 [1.81, 2.85].
Conclusion: The evidence is currently insufficient on this issue, especially on long-term use of mobile phone. Neither a definite answer nor a clear explanation may be offered for the relationship. And larger prospective trials are warranted.