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

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.

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.

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.

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.