No Risk of Eye Cancer
Cell phones do not increase the risk of developing eye cancer, at least for the first ten years of use, according to a group of German researchers led by Andreas Stang at the Martin-Luther-University of Halle-Wittenberg in Halle. This marks a reversal. Eight years ago, Stang reported a possible association in a smaller and less detailed study (see MWN, J/F01, p.9).
This new result is "inconsistent" with his first study, Stang writes in the Journal of the National Cancer Institute (JNCI). That earlier study had only 118 cases of melanoma of the eye and used a "crude exposure assessment" while the new study has 459 cases, with a "very detailed exposure assessment," Stang adds. A questionnaire developed by the Interphone study group was used to assess mobile phone use. The JNCI paper was posted on the journal's Web site on January 13 and will appear in its January 21 issue.
Most other epidemiological studies have not found cancer risks after less than ten years of mobile phone use, though there are indications that longer and more intense cell phone use might lead to a higher incidence of glioma, acoustic neuroma and parotid gland tumors.
Stang declined to offer an opinion about possible long-term melanoma risks. "It would only be wild speculation," he told Microwave News. But, he added, "As long as we do not have empirical data it would be wise to be cautionary." Stang and Karl-Henz Jöckel, his colleague and coauthor, believe that "we should be especially careful with children."
Peter Inskip, an epidemiologist at the National Cancer Institute, agreed that the risks from ten or more years of cell phone use are still open. But, in an interview, Inskip noted that: "I know of no reason to expect there to be an elevated risk for longer observation periods" [his emphasis].
In a commentary that accompanied Stang's 2001 paper, Inskip argued for a "cautious interpretation" of the melanoma risk. Inskip cited the small size of Stang's study, the rough exposure assessment as well as lack of attention to possible confounders. When asked about Stang's new finding, Inskip stated that he appreciated having "stronger information" in the published literature.
A year after Stang's first paper, Danish-U.S. researchers led by Chrisoffer Johansen of the Danish Cancer Society and John Boice of the International Epidemiology Institute reported that they could not find any support for an elevated risk of malignant melanoma of the eye among Danish mobile phone users.
The new paper may be downloaded at no cost. Stang explained that he and Jöckel had paid the journal's fee to allow open access: "We wanted to be sure that everybody in the world has the chance to read the paper."