Hamano, Hirofumi

Importance Head and neck cancer (HNC) accounts for nearly 1 million new cases and approximately half a million deaths annually worldwide, representing a substantial global health burden. Despite an overall decline in mortality in many regions, patterns vary across anatomical subsites and countries. Objective To evaluate international and national mortality trends in HNC and its major anatomical subsites from 2001 to 2023. Design, Setting, and Participants This observational epidemiologic study analyzed population-based mortality data from the World Health Organization (WHO) Mortality Database for 73 countries between 2001 and 2023. Data collection was conducted in May 2025, and the data were analyzed between May and October 2025. Eligible countries had medium- to high-quality vital registration data. Age-standardized mortality rates (ASRs) were calculated using the new WHO World Standard Population. Country-specific trends from 2010 to 2023 were assessed using joinpoint regression among countries with at least 7 years of available data. Main Outcomes and Measures ASRs and average annual percentage change in HNC mortality overall and by anatomical subsite using population-based analysis. Results From 2001 to 2023, 2 000 066 HNC-related deaths (450 657 females; 1 549 409 males) were recorded. Internationally, ASRs decreased by 38.9%, with greater reductions among male individuals than among female individuals. Substantial divergence was observed across subsites: laryngeal cancer mortality decreased markedly (−50.1%), whereas increasing trends in oropharyngeal cancer mortality were observed in many countries in recent years, particularly in high-income countries such as the UK (average annual percentage change, 4.30%) and the US (average annual percentage change, 3.26%). Conclusions and Relevance Results of this study suggest that, although overall HNC-related ASRs have declined internationally, marked variation across subsites and countries persists. The contrasting trends between laryngeal and oropharyngeal cancers underscore the need for subtype-specific prevention strategies and continued global surveillance.

Background and Aims: Biliary tract cancers (BTCs), including intrahepatic cholangiocarcinoma (iCCA), extrahepatic cholangiocarcinoma, gallbladder cancer, and ampullary cancer, exhibit poor prognosis. This study examined temporal trends in mortality due to BTCs and their major subtypes at international, regional, and national levels. Approach and Results: This observational study used the World Health Organization mortality database. Locally weighted regression (LOESS) was used to produce a smoothed curve of long-term international and regional BTC and major subtype-related mortality rates in 2000–2022 based on available data from countries. Trends in age-standardized mortality rates (ASRs) during 2013–2022 for individual countries were examined using joinpoint regression analysis. Internationally, LOESS-smoothed ASRs per 100,000 population due to BTCs were 2.8 (95% CI: 2.5–3.1) in 2000, and 2.7 (2.3–3.1) in 2022. LOESS-smoothed BTC-related ASRs were the highest in the Western Pacific region at 4.2 (1.8–6.6) in 2022, compared with those in the European and American regions at 2.6 (2.3–2.9) and 2.2 (1.8–2.6), respectively. Among major subtypes, LOESS-smoothed ASRs due to iCCA increased by 120.0%, those due to gallbladder cancer decreased by 45.5%, and those due to extrahepatic cholangiocarcinoma remained stable between 2000 and 2022. Disparities in BTC and major subtype-related ASR trends were observed between countries during 2013–2022, with iCCA-associated ASRs showing increasing trends in many countries. Conclusions: Although internationally estimated BTC-associated ASRs showed a stable trend over the last 2 decades, a large increase in estimated iCCA-associated ASRs necessitates developing effective screening for high-risk individuals and disease management strategies.