Study-Increased Brain Tumors from all phones-inconsistent but troubling

[Guest guest]

_http://www.microwavenews.com/CEFALO.html_

(http://www.microwavenews.com/CEFALO.html)

July 27, 2011 (updated July 28)

European Study Reports No Brain Tumor Risk

Among Young Cell Phone Users

Once Again, the Results Are Confusing

Here's the golden rule for all cell phone cancer studies: Nothing comes

easy.

The _first study_

(http://jnci.oxfordjournals.org/content/early/2011/07/27/jnci.djr244.abstract)

to look at brain tumors among children and teenagers

who have used cell phones came out today and it shows no increased risk.

Well, actually, the study, known as CEFALO, does indicate a higher risk —the

problem is that it found a higher risk for all the kids who used a phone

more than once a week for six months, regardless of how much time they spent

on the phone. Because the risk does not go up with more use, the CEFALO

team argues that the results argue against a true association.

" The pattern of results looks to me as though there isn't a causal

relationship in term of increased risk with long-term use, " _ Röösli_

(http://www.swisstph.ch/no_cache/about-us/staff/detail-single-all/staff/71/marti\

n-r

oeoesli.html) told Microwave News. Röösli, of the Swiss Tropical and

Public Health Institute at the University of Basel, ran the Swiss component of

CEFALO. The other participating countries are Denmark, Norway and Sweden.

The results were posted today on the Web site of the Journal of the National

Cancer Institute (JNCI).

The higher risks seen in CEFALO among 7 to 19 year olds are the opposite

of those seen in last year's _Interphone study_

(http://www.microwavenews.com/Interphone.Main.html) . Interphone showed a

systematic lower risk among

all users of cell phones, except for those who were the most highly exposed.

Practically no one believes that the protective effect of cell phones seen

in Interphone is real. Yet, some observers are not willing to discount the

elevated risks seen in CEFALO.

" It's hard to believe studies that give you such bizarre results, " said

_Sam Milham_ (http://www.sammilham.com/) . " CEFALO does not have a random

distribution of odds ratios [ORs]. If anything, it tells me that there might

be a cancer risk. " Milham, the epidemiologist who first linked occupational

exposures to EMFs to leukemia some 30 years ago, is the author of Dirty

Electricity.

" The Interphone study was unusual in having ORs that were largely less

than one and the CEFALO study is unusual in the large number of ORs exceeding

one, " said _ Tarone_ (http://www.iei.us/faculty.html#senior) of the

International Epidemiology Institute (_IEI_ (http://www.iei.us/) ) in an

e-mail to Microwave News. " These findings are peculiar, but they certainly

don't support a causal relationship. " Tarone, together with _ Boice_

(http://www.vicc.org/dd/display.php?person=boicej_compuserve.com) , wrote an

_editorial_

(http://jnci.oxfordjournals.org/content/early/2011/07/27/jnci.djr285.extract)

that accompanies the CEFALO paper in JNCI. Both Tarone and Boice

are alumni of the National Cancer Institute.

" Consistent with virtually all studies of adults exposed to [RF

radiation], no convincing evidence was found [in CEFALO] that children who use

cell

phones are at higher risk of developing a brain tumor, " Boice and Tarone

state in their editorial.

_ Moskowitz_ (http://sph.berkeley.edu/faculty/moskowitz.php) of the

University of California Berkeley School of Public Health sees it

differently. " CEFALO makes for compelling evidence of an increased risk, " he

said.

Moskowitz points out that the study fell short of the _planned number of

subjects_

(http://journals.lww.com/epidem/Fulltext/2006/11001/CEFALO_A_Case_Control_Study_\

of_Brain_Tumors_in.167.aspx) : Instead of 550 cases of children

with brain tumors, there are only 352. " Had they ended up with the desired

number of cases, it is highly likely that the results would have been

statistically significant, " he said.

Röösli readily concedes that it's difficult to interpret the study

findings. " I struggled when I saw the results, " he said. " We talked a lot about

it

within the CEFALO study group, and we asked whether it's an indication of

an association or a systematic problem, or is it just chance? " In the end,

Röösli became convinced that it was unlikely that the elevated odds ratios

are indicative of a real risk. " There is something going on, but honestly I

think it's a systematic error or chance, " he said. What Röösli finds most

convincing is the fact that the overall incidence of brain tumors has not

been spiking up. (He cites the incidence rate in Sweden, between 1990 and

2008, reproduced in Figure 1 of the paper.) " Plausibility is very important

in epidemiology, " he said. " We must ask whether the results are plausible

given what is going on in the world. We may not be able to prove that the

data are wrong but we can show from the incidence data that, if such a risk

were true, the rates would have increased. So something must be wrong. "

Röösli and Tarone say that at least one clear lesson has been learned from

CEAFALO and Interphone: There is no point doing any more retrospective

_case-control studies_ (http://en.wikipedia.org/wiki/Case-control_study) . " If

I knew five years ago what I know now, I would not have started this

study, " Röösli said. " _Prospective studies_

(http://en.wikipedia.org/wiki/Prospective_cohort_study) would make more sense. "

" In my opinion, the peculiar patterns of results of both [CEFALO and

Interphone] provide support to a growing consensus that the possible

association

between brain cancer and cell phone use cannot be reliably studied using

case-control studies, " said Tarone. He added that the CEFALO results are

" reassuring " but that " continued vigilance is necessary. "

Here are some of the other results in CEFALO that are not easily

explained:

• Why is Norway the only country for which the kids had an OR of less than

1? (see Table 3)

• Why did the control subjects " unexpectedly " overestimate their use of

the phones much more than the cases? (For instance, cases overestimated the

duration of their calls by 52% on average and controls by 163%. See the

_paper_ (http://onlinelibrary.wiley.com/doi/10.1002/bem.20651/abstract) on

possible sources of error by the CEFALO group, published in the July issue of

Bioelectromagnetics.)

• Why is the OR for astrocytomas and other gliomas quite a bit lower than

for other types of brain tumors? (see Table 3)

• Why are the risks generally higher on the side of the head opposite to

the one the phone was used (contralateral)? (see Table 5)

• Why are the risks for tumors in the center of the brain or for those of

unknown location much lower than those on either side? (see Table 5)

The results of the next major study on cell phone tumor risks to children —

from the _Mobi-Kids_ (http://www.mbkds.net/) project— are a long way off.

Threre are two more years of field work to complete, said _beth

Cardis_ (http://www.creal.cat/creal/quisom/en_info_user.html?idusuari=ecardis) ,

the project leader.

The paper will appear in the August 17th issue of JNCI.

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