Auvinen A, Hietanen M, Luukkonen R, Koskela R-S (2002)
The Finnish Cancer Registry was used to identify all 398 cases of brain tumour and 34 of salivary gland cancer diagnosed in 1996. Five age- and sex-matched controls were selected for each tumour case from the Population Registry Centre of Finland. The authors also compared the location and tumour subtype among case with and without cellular phone subscription. Exposure to cellular phone was identified from lists of phone subscribers. Type of subscription (analog vs digital) and start and end date of subscription were also available. Other factors including place of residence, socioeconomic status, and occupation were also considered in the analysis.
Thirteen per cent of brain tumour cases, 12 % of salivary gland cancer cases, and 11 % of controls had ever had a personal subscription to a cellular telephone network. Average duration of subscription was 2-3 years for the analog system, but less than 1 year for the digital system.
Overall there was no association between cellular phone use and brain tumours or salivary gland cancer. Gliomas, a particular brain tumour type, had a weak association with analog phone use (OR 1.3-3.4), but this was based on only 26 cases. There was no difference in tumour type or location between exposed and unexposed glioma cases.
The main weakness of this study is the lack of detailed information on exposure, since the authors could not confirm that the subscriber was the actual user of the phone. They also had no information on duration and frequency of calls, or on cellular phones provided by companies to their employees.