INTERPHONE Publication – Scientific Summary and Key Points
On 17th May 2010, the International Agency for Research on Cancer (IARC) published the results of the INTERPHONE combined analysis for glioma or meningioma in the paper titled "Brain cancer risk in relation to mobile telephone use : results of the INTERPHONE international case–control study"
The following summary and key points are taken from the INTERPHONE paper
- Overall, no increase in risk of glioma or meningioma was observed with use of mobile phones. There were suggestions of an increased risk of glioma at the highest exposure levels, but biases and error prevent a causal interpretation. The possible effects of long-term heavy use of mobile phones require further investigation.
- A reduced odds ratio (OR) related to ever having been a regular mobile phone user was seen for glioma [OR 0.81; 95% confidence interval (CI) 0.70–0.94] and meningioma (OR 0.79; 95% CI 0.68–0.91), possibly reflecting participation bias or other methodological limitations
- No elevated OR was observed >10 years after first phone use (glioma: OR 0.98; 95% CI 0.76–1.26; meningioma: OR 0.83; 95% CI 0.61–1.14). ORs were <1.0 for all deciles of lifetime number of phone calls and nine deciles of cumulative call time. In the 10th decile of recalled cumulative call time, >1640 h, the OR was 1.40 (95% CI 1.03–1.89) for glioma, and 1.15 (95% CI 0.81–1.62) for meningioma; but there are implausible values of reported use in this group
- ORs for glioma tended to be greater in the temporal lobe than in other lobes of the brain, but the CIs around the lobe-specific estimates were wide. ORs for glioma tended to be greater in subjects who reported usual phone use on the same side of the head as their tumour than on the opposite side.
Interpretation of results
- We have no certain explanation for the overall reduced risk of brain cancer among mobile phone users in this study, although selection bias is almost certainly a contributor.
- The possibility of raised risk in heavy users of mobile phones is an important issue because of their ever-increasing use. Moreover, few subjects in our study had used mobile phones for 12 years; therefore, our results are uninformative with respect to lag periods longer than this.
- There is some evidence that very high users experienced excess risk of glioma, but that evidence is inconclusive because of possible bias.
Consistency with previous research
- Our results are consistent with most of the research published to date.
- A large Danish cohort study of mobile telephone subscribers, with an average follow-up time of 8.5 years, found no increased risk of brain tumours in subscribers of > 10 years.
- Much biological research has been done in recent years on possible biological effects of RF fields. This work covers in vitro and in vivo exposure, alone and in combination with other physical or chemical agents, and has found no evidence that RF fields are carcinogenic in laboratory rodents or cause DNA damage in cells in culture.
Conclusions from main paper
- This is the largest study of the risk of brain tumours in relation to mobile phone use conducted to date and it included substantial numbers of subjects who had used mobile phones for > 10 years.
- Overall, no in-crease in risk of either glioma or meningioma was observed in association with use of mobile phones.
- There were suggestions of an increased risk of glioma, and much less so meningioma, at the highest exposure levels, for ipsilateral exposures and, for glioma, for tumours in the temporal lobe. However, biases and errors limit the strength of the conclusions we can draw from these analyses and prevent a causal interpretation.