An update in international trends in incidence rates of thyroid cancer, 1973-2007.

PURPOSE

Over the past several decades, there has been a reported increase in the incidence of thyroid cancer in many countries. We previously reported an increase in thyroid cancer incidence across continents between 1973 and 2002. Here, we provide an update on the international trends in thyroid cancer between 2003 and 2007.

METHODS

We examined thyroid cancer incidence data from the Cancer Incidence in Five Continents (CI5) database for the period between 1973 and 2007 from 24 populations in the Americas, Asia, Europe, Africa and Oceania, and report on the time trends as well as the distribution by histologic type and gender worldwide.

RESULTS

The incidence of thyroid cancer increased during the period from 1998-2002 to 2003-2007 in the majority of populations examined, with the highest rates observed among women, most notably in Israel and the United States SEER registry, at over 14 per 100,000 people. This update suggests that incidence is rising in a similar fashion across all regions of the world. The histologic and gender distributions in the updated CI5 are consistent with the previous report.

CONCLUSIONS

Our analysis of the published CI5 data illustrates that the incidence of thyroid cancer increased between 1998-2002 and 2003-2007 in most populations worldwide, and rising rates continue in all regions of the world.