Invasive cancer statistics in Japan were compiled for the Fukushima Cancer Registry database and published by the National Cancer Center Japan. If we review av

Invasive cancer statistics in Japan were compiled for the Fukushima Cancer Registry database and published by the National Cancer Center Japan. If we review average annual percent change on Thyroid cancer incidence, there was a more or less stable value between 2008 and 2011. Then in 2012 there is a sudden increase of 10,8% on Fukushima, versus a 3,7% for the whole Japan in the same year [1]. Some increase is normal in a population that is growing and aging but a jump, not so much. We even have a control population: The Tochigi prefecture (at the South of Fukushima and bordering it). This landlocked prefecture has a big industrial complex, including a strong sector of X-ray machines makers. Tochigi has the lower increase on Thyroid cancer of the three between 2011 and 2012 (3,2% increase). [1] The death ratio didn't changed, but people that is diagnosed with cancer does not die immediately, so just looking for mortality increase that year is a deceptive measure. So, something happened in 2012 that increased Thyroid cancer on Fukushima more than in the rest of Japan. Lets assume that we forget all about the elephant in the room, and past experiences where radioactivity accidents typically increased thyroid cancers. How would you explain that? Any alternative hypothesis? ----------------- [1] Shibata A, Saji S, Kamiya K, Yasumura S. Trend in Cancer Incidence and Mortality in Fukushima From 2008 Through 2015. J Epidemiol. 2021 Dec 5;31(12):653-659 (The article covers only up to 2015 to remove artifacts from 2016 when the way to report cancer changed, causing another increase on the registers).