Background/Objectives: Thyroid cancer incidence has risen in both the United States and Canada, despite differing healthcare systems. While overdiagnosis likely partly explains this trend in adults, its impact on younger populations is unclear. We used the North American Association of Central Cancer Registries, which included 133,808 thyroid cancer cases from the United States and Canada, to assess incidence trends among pediatric, adolescent, and young adult (PAYA) populations. Methods: Age-adjusted incidence rates (AAIR) per 100,000 person-years (PY) were compared using rate ratios (RR), stratified by sex, age, race/ethnicity (United States only), and histology. Joinpoint regression estimated annual percentage changes (APC) and average APCs (AAPC) in AAIRs. From 1995 to 2014, thyroid cancer incidence increased by 137%. Significant increases occurred across all age groups (0–14, 15–24, 25–34, 35–39 years). The rate increase was highest for papillary thyroid cancer (AAPC = 5.50, 95% CI 5.06, 5.94), and among individuals aged 35–39 years (AAPC = 5.99, 95% CI 4.84, 7.15). Of racial/ethnic groups in the United States, non-Hispanic White individuals had the highest AAIR (6.22 per 100,000 PY). Mortality has changed minimally. Conclusions: Over the past two decades, thyroid cancer incidence has increased in individuals under 40. While evidence suggests that overdiagnosis primarily accounts for this trend, other contributing factors cannot be ruled out. Further research and surveillance of the drivers of increased incidence are critical.
背景/目的：尽管美国和加拿大的医疗体系存在差异，但两国甲状腺癌发病率均呈上升趋势。虽然过度诊断可能是成人中这一趋势的部分原因，但其对年轻人群的影响尚不明确。我们利用北美中央癌症登记协会的数据（涵盖美国和加拿大133,808例甲状腺癌病例），评估了儿童、青少年和青年（PAYA）人群的发病率趋势。方法：按性别、年龄、种族/民族（仅美国）和组织学类型分层，使用率比（RR）比较每10万人年（PY）的年龄调整发病率（AAIR）。采用连接点回归估计AAIR的年度百分比变化（APC）和平均APC（AAPC）。结果：1995年至2014年间，甲状腺癌发病率增加了137%。所有年龄组（0–14岁、15–24岁、25–34岁、35–39岁）均出现显著增长。其中甲状腺乳头状癌的增长率最高（AAPC = 5.50，95% CI 5.06, 5.94），35–39岁人群的增长率最为突出（AAPC = 5.99，95% CI 4.84, 7.15）。在美国各族裔群体中，非西班牙裔白人的AAIR最高（每10万PY 6.22例）。死亡率变化极小。结论：过去二十年间，40岁以下人群的甲状腺癌发病率持续上升。现有证据表明过度诊断是主要驱动因素，但其他影响因素仍不能排除。进一步研究和监测发病率上升的驱动因素至关重要。
肿瘤(癌症)患者之家