Thirty-Year Trends (1991-2020) in Head and Neck Cancer Incidence Rates: Hanoi Cancer Registry, Vietnam

Head and neck cancers (HNCs) remain a major contemporary public health challenge, yet few population-based studies have examined the long-term incidence trends of HNCs in low- and middle-income countries.

Using International Classification of Diseases, 10th Revision code data from the Hanoi Cancer Registry (1991-2020), we examined 30-year trends in HNC incidence rates using age-standardized incidence rates (ASIRs). Incidence rates were stratified by sex, primary site, 5-year age groups, and within six 5-year diagnostic periods spanning 1991-1995 through 2016-2020. Ratio-based imputation was applied to account for expansions in Hanoi's incorporated administrative areas. Temporal trends were assessed using joinpoint (JP) regression to estimate average annual percent changes and age-period-cohort models were used to evaluate independent age, period, and birth cohort effects.

A total of 19,589 HNC cases were identified (74% men). ASIRs increased from 10.9 per 100,000 in 1991-1995 to 18.8 in 2006-2010, and then declined to 11.8 in 2016-2020. The proportion of male cases of HNCs increased from 62.2% in 1991-1995 to 79% in 2016-2020. Nasopharyngeal and sinonasal cancers decreased from 68% to 21% of male cases and from 59% to 36% of female cases. Oral cavity cancers increased proportionally among men. JP and age-period-cohort analyses indicated a strong period effect peaking in 2006-2010 and declining risk among post-1950 birth cohorts.

Over the 30-year study period, we observed a growing male predominance of HNCs, a shift in burden toward oral cavity tumors over time, and a widening male-to-female disparity in several HNC primary site cancers. Our findings highlight an evolving epidemiologic transition in Northern Vietnam, underscoring the need for strengthened surveillance, screening, and targeted prevention and control strategies.