• 05 SEP 05
    • 0

    Commentary from Lloyd Morgan

    Dear EMFacts community,
    Please see my various comments within the text below (in bold itallics).

    Best regards to all,
    Lloyd Morgan
    Director, Central Brain Tumor Registry of the United States

    [For identification purposes only. All statements are mine and mine alone and do not represent positions or opinions if the Central Brain Tumor registry of the United States.]

    Comments on message #202: ‘Power Watch analysis on that acoustic neuroma study’ which was posted to EMFacts Consultancy.

    The analysis by PowerWatch, http://www.powerwatch.org.uk :

    British Journal of Cancer advance online publication 30 August 2005; doi:10.1038/sj.bjc.6602764. Mobile phone use and risk of acoustic neuroma: results of the Interphone case-control study in five North European countries

    The media widely and incorrectly reported that the largest ever study into mobile phone use and brain cancer showed no increase in the first 10 years of use. In fact, this only applied to a rare form benign tumour, Acoustic Neuroma, and that the study did find an increased risk after 10 years of use of 1.8-fold – i.e. almost a doubling in risk. This misreporting seems to have been due to the content of an email send to the media by the Science Press Officer of Institute of Cancer (ICR) Research and the fact that it was almost impossible to get hold of a copy of the actual paper before the news embargo deadline by which time most people had written, filmed and filed their stories.

    [Lloyd]: I believe, from the immediacy of the media response that this is based is far more than a single email sent by the Press Officer of the Institute of Cancer (ICR) as I will explain below. If anyone has a copy of the ICR email it will be greatly appreciated. If you have the distribution list for the ICR email that would be even better.

    I learned about this paper through an American TV broadcast of BBC World News (the day before the paper was released USA, time and just after midnight UK time on the day of the release). I immediately went to their website and found 64 news stories. The next morning, USA time, there were 154 news stories.

    A common practice is for a press release and a copy of the “science” paper is released by the science journal to the media at least a week, sometimes a month, before publication. Any reports are embargoed before the publication date (failure to observe the embargo will mean that your media will no longer be given pre-released information) of the article. So the stories are written for release on the day the paper is “published.”

    It is also important to understand that this study had major funding from the cellphone industry.

    Most often, the stories are, at best, re-writes of the press release. It is rare that any reporter actual reads the paper itself.

    Acoustic Neuromas are very slow growing and few are diagnosed before 10 years have elapsed from the original initation of the cancer. Some take up to 30 years to be diagnosed. So, it is most unlikely that any study would find a significant change in incidence levels before about 10 years had passed. Looking at the results of this study in that light, it confirms some other studies’ findings that, after 10 years use, there is a significant increase in Acoustic Neuromas on the side of the head where the mobile phone user victim usually held their handset.

    [Lloyd]: Acoustic neuroma are referred to by the oxymoronic term, “benign” brain tumor. These “benign” tumors almost always result in deafness in the ear that has the tumor. If not removed or otherwise treated they are likely to cause death. At least 50% of the time when they are surgically removed facial paralysis is the result because the facial nerve wraps around the acoustic nerve. The dictionary defines benign as harmless.

    These tumors are also called Schwannomas because they are a tumor of the Schwann cells surrounding the neurons.


    There is public concern that the use of mobile phones could increase the risk of brain tumours. A number of studies have found a significant increase in the incidence of acoustic neuromas, especially on the same side of the head where the mobile handset was regularly held. Other studies have not. These are listed in the discussion section of this new paper.

    [Lloyd]: The only cellphones studies which have not found an increased risk of acoustic neuromas are studies that did not have a sufficient number of cases for a reasonable latency time to find a risk. All studies, including this one, that have a sufficient number of cases with over 10 years of exposure have found an increased risk of acoustic neuroma (up to 8+ fold risk increase, depending on the study).

    The age-corrected incidence of brain cancer in the UK has been rising at about 1.7% per year over the last 25 years [2]. Nobody has identified the reasons for this increase which pre-dates the take up of mobile phones but does not pre-date the rise of high-frequency electronics and the “wireless revolution”. We are not suggesting that electromagnetic fields are responsible for anything like this entire rise, but they are certainly on the “suspects” list as a possible causal factor. Most solid tumours take over five years to develop to the point of diagnosis, and many take 10 to 20 years to do so.

    This latest study was press-released with the claim that it had failed to find an association between brain-cancer and mobile phone use. In fact, it only considered acoustic neuroma, a relatively rare (about 6% of brain tumours), very slow-growing, benign tumour that is generally understood to take between 10 and 30 years to develop to the stage when it is diagnosed [3]. This new study did find a 1.8-fold increased risk (CI 1.1-3.1), after 10 years phone use, of acoustic neuromas developing in the side of the head where the mobile phone handset was usually held. So, it was quite wrong to Press Release it as proving that mobile phone use is not associated with the development of brain cancer.

    [Lloyd]; In the USA, acoustic neuroma account for a little over 4% of all brain tumors (see www.cbtrus.org).

    This study suggests a strong selection bias between cases of acoustic neuromas and controls (matched to the cases by age, gender, location and economic class to the cases). Where 15% of the cases selected for inclusion in the study did not participate in the study some 48% of the controls did not participate. It is reasonable to assume that there was a much higher proportion of the controls who agreed to participate in the study used cellphones than the controls who chose not to participate. Such a selection bias will substantial reduce the risk.

    Another way to analyze a study is a binomial analysis. If there is no risk, the there should be a roughly equal number of odds ratios greater than one (increase risk) as there are odds ratios less than one (reduced risk). In this study every single case of reported odds ratios greater than one (8) occurs for exposures greater than 10 years. Using Table 2 for a binomial analysis, which has 12 odds ratios below one and 2 odds ratios above 1, results in the probability of 0.65% that there no risk of an acoustic neuroma from cellphone use. Conversely, it says that there is a 99.35% chance that using a cellphone protects one from having an acoustic neuroma. This non-sensical result in itself indicates selection bias.

    In contrast a study by Hardell et al., (“Case-Control Study on Cellular and Cordless Telephones and the Risk of Acoustic Neuroma or Meningioma in Patients Diagnosed 2000-2003; Neuroepidemiology 2005;25: 120-128) found risk of 5.0 fold with strong statistical significance (99.92%). The equivalent non-participation rates in this study was 11% of cases and 16% of controls.

    The data from the Swedish cases was published earlier [4, 5] and that paper showed a 3.9-fold increased risk (CI 1.6-9.5), after 10 years phone use, of acoustic neuromas developing in the side of the head where the mobile phone handset was usually held.

    Some other Swedish studies [e.g. 6] have also implicated mobile phone and extensive cordless phone over a long time with the incidence of other brain tumours.

    We, at Powerwatch, are more concerned about the possibility that regular mobile and cordless phone use stimulates the development of early-onset (pre-age 60) dementias, the incidence of which is significantly rising at present.

    [Lloyd]:I believe that, based on papers already published that the incidence of brain tumors from cellphone use may increase to those of breast and prostate cancer. This would mean that somewhere between one person in 6 to one in 8 will have a brain tumor in the lifetime. And yes, dementia is also a real possibility but there are zero human epidemiological papers that have looked at this risk.

    Our advice stays the same. Children really should not use a mobile phone other than in a real emergency, and adults should minimise their use – wait until you can get to a land-line phone, send a short text message, or use a air-pipe hands-free kit and hold the handset away from your body when making a phone call.

    [Lloyd]:We know from copious data for other known carcinogens that children are at far higher risk of a cancer for a given exposure than adults. The usual assumption is that this is because children’s cells are still dividing at very high rates compared to adults.

    – Alasdair Philips

    [1] Schoemaker M J, et al, (2005) Mobile phone use and risk of acoustic neuroma: results of the Interphone case-control study in five North European countries, British Journal of Cancer, September 2005.

    Available from: http://www.nature.com/bjc/journal/vaop/ncurrent/abs/6602764a.html

    [2] http://www.statistics.gov.uk/StatBase/Product.asp?vlnk=4822

    [3] United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). Sources and effects of ionizing radiation. UNSCEAR 2000. Report to the General Assembly, with scientific annexes. New York.

    [4] Lonn S, et al, (2004) Mobile phone use and the risk of acoustic neuroma, Epidemiology, Vol 15, No 6, 653-659, November 2004.

    [5] Lonn S, et al., (2005) Long term mobile phone use and brain tumour risk, American Journal of Epidemiology, vol 161, No.6, 526-535.

    [6] Hardell L, Mild K, Carlberg M, (2003) Further aspects on cellular and cordless telephones and brain tumours. International Journal of Oncology 22: 399-407.

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