Temporal trends and regional inequalities in oral cancer in Brazil, 2013-2030: An ecological time-series analysis

PURPOSE: This study analyzed temporal trends, the impact of the COVID-19 pandemic, and projections up to 2030 for oral cancer incidence and mortality rates in Brazil, stratified by sex and macro-region. METHODS: This population-based observational study used secondary data from the Department of Informatics of the Brazilian Unified Health System (DATASUS) and the Hospital Information System (SIH/SUS), covering the period from 2013 to 2022. Malignant neoplasms of the oral cavity and major salivary glands (C00-C08, ICD-10) were included. Age-standardized incidence (ASIR) and mortality (ASMR) rates were analyzed using Prais-Winsten linear regression and classified according to the Annual Percentage Change (APC), with significance set at p < 0.05. Projections to 2030 were estimated using double exponential smoothing, and the pandemic's impact was assessed through the ratio of observed-to-predicted rates (RR) for 2020-2022. RESULTS: The study recorded 40,078 deaths and 92,411 cases, 70.8% of which occurred in men, with the highest concentration in individuals aged 55-64 years. The trends revealed a significant increase in incidence across all macro-regions, particularly in the North and South regions, whereas mortality rates remained stable. During the pandemic, an apparent reduction in cases (RR <1) was observed, suggesting underreporting and diagnostic delays. The projections indicate a continuous increase in incidence and a slight rise in mortality through 2030. Limitations include reliance on secondary data that are subject to underreporting and delays, especially during the pandemic. CONCLUSION: These findings highlight the worsening of regional inequalities and underscore the urgency to strengthen prevention, screening, and early diagnosis policies, particularly in socially vulnerable contexts.