Study reports a possible association between mobile phone use and thyroid cancer for specific gene types
This population-based case-control study compared mobile phone use with the incidence of thyroid cancer diagnosed between 2010 and 2011 in Connecticut. The study included 440 cases of histologically confirmed incident thyroid cancers and 460 controls, with genotyping information for 823 single nucleotide polymorphisms (SNPs) in 176 DNA genes. All participants, including cases and controls, were interviewed using a standardized questionnaire to collect information on mobile phone use and the responses were used to classify cases and controls as users or non-users. Blood samples were provided for DNA analysis. The authors reported that the study found a statistically significant association between cell phone use and thyroid cancer for certain SNPs, implying a genetic susceptibility to thyroid cancer due to mobile phone use.
This study built upon a previous study by the same authors (Lou et al, 2019) that found no association between mobile phone use and thyroid cancer in the same study group. One of the advantages of using a study group within the period 2010-2011 was that it is much easier to separate mobile phone users from non-mobile phone users. A disadvantage of using this study group was that the exposure data had to be gathered through surveying the participants. The information required was from a point in the distant past where recall bias may effect some of the results. The control group consisted of a higher proportion of males to females than the case group. This may have significant implications on the reliability of the results due to the higher occurrence of thyroid cancer in of woman. Further, mobile phones were not the only exposures to radio waves during the time of exposure assessment. A good example of this was the widespread use of cordless phones which are used in the same manner (held to the head) and have a similar level of exposure.