Trends in tonsil cancer incidence rates in the US: 2000-2014

Presentation: C071
Topic: Pharynx / Larynx Cancer
Type: Poster
Date: Thursday, April 19, 2018
Session: 9:00 AM - 7:00 PM
Authors: Elizabeth Handorf, Miriam Lango, MD
Institution(s): Fox Chase Cancer Center

Introduction: As the prevalence of smoking has declined, the incidence rates of tobacco-related malignancies have declined; tobacco-related malignancies have become increasingly concentrated in populations that are subject to disparities in care, including the poor, racial and ethnic minorities, and rural populations. The incidence of HPV-related cancers is increasing, but incidence trends across geographic regions have not been well described.

Methods: Age-adjusted incidence rates and trends for tonsil squamous cell carcinomas (2000-14) from Surveillance, Epidemiology, and End Results (SEER 18) were evaluated using SEER Stat 8.3.4 and Joinpoint, for pairwise comparison. Average annual percentage changes (AAPCs) were compared across specified geographic regions and median family income quartiles during this time period.

Results: The age-adjusted incidence rates for tonsil squamous cell carcinoma were highest in the East and Northern Plains, and the lowest in the Southwest. The Kentucky registry had the highest age-adjusted incidence (2.2/100,000, 95% confidence interval: 2.1-2.3); the Utah registry had the lowest (0.9/100,000,95%CI: 0.8-1.0). Higher incidence rates were seen in geographic regions with lower median family incomes. Incidence rates increased in all income quartiles during this period. However, significantly greater increases were seen in the lowest relative to the highest income quartile: average annual percentage change (AAPC) 3.2 (2.0-4.3) versus 1.9 (1.4-2.4), p=.001, respectively.

Conclusion: Significant variations in tonsil cancer incidence rates were observed. Tonsil cancer incidence rates, greater in regions with lower median incomes, also increased at significantly greater rates in such areas. High-risk areas should be the focus of prevention efforts.