Thyroid cancer burden on rise in US, Europe
Click Here to Manage Email Alerts
A new study has found an increase in thyroid cancer incidence rates over a 30-year period in many countries, including the United States and several countries in the European Union.
For the analysis, James Schuster-Bruce, BSc, MBChB, specialist registrar in ear, nose and throat and head and neck surgery at St. George’s University Hospitals NHS Foundation Trust in London, and colleagues aimed to examine trends in mortality, incidence and disability-adjusted life-years associated with thyroid cancer from 1990 to 2019. The researchers looked at 15 countries in the European Union along with the United States, Australia, Canada and Norway (EU15+).
The observational cross-sectional analysis featured data from the Global Burden of Disease Study database. Researchers extracted age-standardized incidence rates, age-standardized mortality rates, and for individual EU15+ countries for each of the years studied, and calculated mortality-to-incidence indexes.
Results indicated that 13 of 19 countries (68%) had a rise in the average annual percentage change in age-standardized incidence rates across the study period (range, 0.2%-2.5%). The two countries with the highest average annual percentage change were Australia (2.5; 95% CI, 2.3-2.7 per 100,000 population) and the United States (1.2; 95% CI, 1-1.3 per 100,000 population).
By using join-point regression analysis, researchers found age-standardized incidence rates mostly leveling off in recent years across most EU15+ nations since 1990. For the United States, the estimated annual percentage change from 2011 to 2019 was zero.
In addition, the only countries with increasing mortality trends and positive average annual percentage change were Australia (0.6; 95% CI, 0.2-1), Denmark (1; 95% CI, 0.8-1.3) and the United States (0.4; 95% CI, 0.4-0.5), whereas the remaining 16 countries displayed negative trends (range, 0.2 to 2.1). Moreover, there was a reduction in all EU15+ countries except Australia, Denmark and the United States.
“We report overall increases in the burden of thyroid cancer across the majority of EU15+ countries between 1990 and 2019, evidenced by plateaus in incidence rates and reductions in mortality and rates,” Schuster-Bruce and colleagues concluded. “However, in a number of countries, including the U.S., there are unfavorable increasing mortality and trends over this time period. Close observation of future time trends in thyroid cancer disease burden should be performed in the context of recent changes in international clinical practice guidelines, which have suggested more conservative diagnostic and management strategies.”
Perspective
Back to Top
The work of Schuster-Bruce and colleagues is an interesting analysis of the Global Burden of Disease Study on the burden and trends of thyroid cancer in selected high-resource countries, including several European countries plus the U.S., Australia and Canada. It confirms the results from previous international studies that found a very large between-country variability of the incidence rates of the disease and a relative homogeneity of the mortality rates. Importantly, the discrepancy between the level of incidence and that of mortality is very large. These are epidemiologic features that have been associated with large overdiagnosis of thyroid cancer.
With respect to the temporal trends, the study shows a general increase in the incidence rates over the period 1990 to 2019, which is also consistent with what was previously reported. Stabilization and/or decline of the incidence trends are, however, surprisingly reported for certain high-incidence countries. For instance, in this study the incidence of thyroid cancer in France and Italy seems to decline from around 2003-2005 until 2019, but this result is not consistent with the “observed” data derived from cancer registries — the most reliable source of cancer data — which conversely show that in these two countries trends were still rising at least up until 2014-2015. It would be interesting to clarify the reasons for the discrepancy between the “observed” data and Global Burden of Disease Study results in term of absolute levels of incidence and trends.
Collapse
Schuster-Bruce J, et al. JAMA Otolaryngol Head Neck Surg. 2022;doi:10.1001/jamaoto.2021.4549.
Read more about
Click Here to Manage Email Alerts