The Increasing Incidence of Thyroid Cancer in Sweden Revisited

Use of the handheld wireless phone emits radiofrequency (RF) radiation and the thyroid gland is one target organ, especially when the smartphone is used. We used the Swedish Cancer Register to study trends of thyroid cancer during 1970-2022. In women the incidence increased statistically significant during that time period with average annual percentage change (AAPC) +1.69%, 95% confidence interval (CI) +1.48, +1.95%. The increase was especially pronounced during 1999-2022 with annual percentage change (APC) +4.35%, 95% CI +3.88, +4.89%. For different age groups APC was highest in women aged 40-59 years yielding APC +5.40%, 95% CI +4.21, +6.86% for the time period 2001-2022. In men AAPC increased during 1970-2022 with +0.94%, 95% CI +0.65, +1.25%. Highest increase was found for the time period 2001-2022 with APC +3.47%, 95% CI +2.52, +4.84%. Regarding different age groups highest APC +4.42%, 95% CI +2.81, +7.34% was found in men aged 40-59 years for the time period 2002-2022. These results support a causation between radiofrequency radiation from the handheld mobile phone and thyroid cancer.