2022年 · 第102卷第48期

In many countries and regions, the incidence of thyroid cancer has increased; However, the mortality rate has been stable at a low level. This epidemiological pattern is largely attributed to over-diagnostic effects. In order to ascertain the magnitude of the problem and the areas most affected by it, it is necessary to analyze the global epidemiological situation in a timely manner. Therefore, the study aims to provide up-to-date assessment data on the global distribution of thyroid cancer incidence and mortality in 2020. The study calculated the age-standardized incidence and mortality per 100,000 person-years of thyroid cancer by sex and 18 age groups from 185 countries or territories extracted from the GLOBOCAN database according to the International Classification of Diseases in Oncology, 10th edition (code C73). Morbidity and mortality estimates are provided by country and 20 world regions as defined by the United Nations and aggregated based on the four-level Human Development Indices (i.e. low, medium, high and very high) of the United Nations in 2020. Globally in 2020, the age-standardized incidence rate of thyroid cancer was 10.1/100,000 for women and 3.1/100,000 for men, and the age-standardized mortality rate was 0.5/100,000 for women and 0.3/100,000 for men. In all cases, the incidence rates in countries with high and very high HDI were 5 times higher than those with low and moderate HDI, while mortality rates were relatively consistent across settings. Incidence varies more than 15 times among women around the world, with the highest rates in the Federated States of Micronesia and French Polynesia (18.5/100,000), North America (18.4/100,000), and East Asia (17.8/100,000, with South Korea reaching 45/100,000). In most countries, mortality rates<1.0/100,000. South Korea has the highest morbidity-to-mortality ratio for both men and women, followed by Cyprus and Canada. The current epidemiological status of thyroid cancer strongly suggests that overdiagnosis has a huge impact in many countries and settings around the globe, confirming that overdiagnosis of thyroid cancer is a global public health problem.

In patients with low-risk differentiated thyroid cancer undergoing thyroidectomy, postoperative¹³¹The application of I is controversial and there is insufficient evidence to demonstrate its benefit. The study was a prospective, randomized, Phase III clinical trial in which patients with low-risk differentiated thyroid cancer who underwent total thyroidectomy were divided into two groups, one who received radioiodine treatment (1.1 GBq) after injection of recombinant human thyroid stimulating hormone (radioiodine group) and the other who did not receive radioiodine treatment after surgery (radioiodine-free group). The differences between the two groups were judged by the presence or absence of functional, structural and biological abnormalities within 3 years. Intergroup differences in the presence of abnormal radioactive iodine uptake lesions requiring subsequent treatment in the whole body scan (only in the radioactive iodine group), abnormal neck ultrasound, and elevated levels of thyroglobulin or thyroglobulin antibodies<5% were considered indifferent, and secondary measures included prognostic factors and molecular characteristics. It was found that of the 730 patients evaluable after 3 years, the rate of no adverse events in the radioiodine-free group was 95.6% (95%CI: 93.0% to 97.5%), and 95.9% (95%) in the radioiodine groupCI: 93.3% to 97.7%), and the difference between the two groups was-0.3% (95%CI：-2.7%~2.2%）。 Adverse events included structural or functional abnormalities in 8 patients and biological abnormalities in 23 patients (25 adverse events). Patients with postoperative serum thyroglobulin levels exceeding 1 μ g/L had the highest frequency of events during thyroid hormone therapy. Molecular alterations were similar in patients with or without adverse events, and no treatment-related adverse events were reported. It is therefore concluded that in low-risk thyroid cancer patients undergoing thyroidectomy, the follow-up strategy without radioactive iodine is not inferior to the one with radioactive iodine in terms of the occurrence of functional, structural and biologically abnormal events at 3 years after surgery.