Thyroid cancer incidence trends by histology in 25 countries: a population-based study
Menée à partir des données de 25 pays sur la période 1998-2012, cette étude analyse l'évolution de l'incidence du cancer de la thyroïde par sous-type histologique
Background : The incidence of thyroid cancer has increased in different populations worldwide inthe past 30 years. We present here an overview of international trends of thyroid cancer incidence by major histological subtypes.
Methods : We did a population-based study with data for thyroid cancer incidence collected bythe International Agency for Research on Cancer (IARC) for the period 1998–2012. Datawere extracted from the Cancer Incidence in Five Continents plus compendium. We selected data for 25 countries that had a population of more than 2 million individuals covered by cancer registration (87 registries in total). Further criteria were that the selected registration areas had to have a proportion of unspecifiedthyroid cancer of less than 10% and analyses were restricted to individuals aged 20–84years. We calculated age-specific incidence rates and age-standardised rates per 100 000 person-years for individuals aged 20 to 84 years, and assessed trends by country,sex, and major histological subtype (papillary, follicular, medullary, or anaplastic)based on absolute changes in age-standardised incidence rates between 1998–2002 and 2008–12.
Findings : Papillary thyroid cancer was the main contributor to overall thyroid cancer in allthe studied countries, and was the only histological subtype that increased systematicallyin all countries, although with large variability between countries. In women, theage-standardised incidence rate of papillary thyroid cancer during 2008–12 rangedfrom 4·3–5·3 cases per 100 000 person-years in the Netherlands, the UK, and Denmark,to 143·3 cases per 100 000 women in South Korea. For men during the same period, theage-standardised incidence rates of papillary thyroid cancer per 100 000 person-yearsranged from 1·2 cases per 100 000 in Thailand to 30·7 cases per 100 000 in South Korea.In many countries in Asia, the increase in papillary thyroid cancer rates in womenwas particularly pronounced after the year 2000; rates stabilised since around 2009in the USA, Austria, Croatia, Germany, Slovenia, Spain, Lithuania, and Bulgaria. Temporaltrends for follicular and medullary thyroid cancer did not show consistent patternsacross countries, but slight decreases were seen for anaplastic thyroid cancer in21 of 25 countries between 1998–2002, and 2008–12. In 2008–12, age-standardised ratesfor the follicular subtype ranged between 0·5 and 2·5 cases per 100 000 women (andbetween 0·3 and 1·5 per 100 000 men), while those for the medullary subtype were alwaysless than 1 case per 100 000 women or men, and for anaplastic thyroid cancer lessthan 0·2 cases per 100 000 women or men.
Interpretation : In the period from 1998 to 2012, the rapid increases in thyroid cancer incidence were observed only for papillary thyroid cancer, the subtype more likely to be found ina subclinical form and therefore detected by intense scrutiny of the thyroid gland.
The Lancet Diabetes & Endocrinology , résumé, 2020