Evaluating Thyroid Cancer Incidence and Minnesotan Residential Radon Concentration

Presentation: AHNS-005
Topic: Endocrine
Type: Oral
Date: Wednesday, May 1, 2019
Session: 1:10 PM - 1:55 PM Scientific Session 1 - Endocrine
Authors: Curtis Hanba, MD, Margaret Engelhardt, MD, Sobia Khaja, MD, Emiro Caicedo-Granados, MD
Institution(s): The University of Minnesota - Department of Otolaryngology

Objectives/Hypothesis: Radon is a potent carcinogen. One’s risk of lung cancer rises nearly 16% for every 2.7 pCi/L increase in daily radon exposure. In 2009, the World Health Organization suggested corrective action to be taken in any home with measured concentrations above 4 pCi/L. Due to the thyroid’s susceptibility to ionizing radiation, and radon’s known carcinogenic properties, we aimed to evaluate the relationship between household radon concentration and thyroid cancer incidence in Minnesota. 

Methods: A county by county compilation of data from The Minnesotan Department of Health’s website was evaluated for thyroid cancer incidence (2009-2013), and household radon concentration (2010-2016). Linear regression evaluated factors contributing to thyroid cancer incidence with a cutoff for statistical significance set at p = 0.05.  

Results: Radon concentrations were reported annually for an average of 19,198 homes for years 2010-2016. On average of 73.5% of homes returned radon concentrations above 2 pCi/L, and 44.1% of homes measured > 4 pCi/L. Minnesotan thyroid cancer incidence averaged 12.5 cases per 100,000. Linear regression analysis identified average radon concentration to significantly impact a county’s incidence of thyroid cancer. (Incidence per 100,000 = 8.78 + 0.656x; 95% CI 0.116 – 1.197; R-20.064; p = 0.018)

Conclusion: Our analysis identified a significant correlation between household radon concentration and the incidence of thyroid cancer in Minnesota. This alarming trend may warrant further investigation regionally or nationally, and further inquiry into the carcinogenic potential of this ubiquitous gas should be pursued. 

Key Words: Radon, Thyroid Cancer, Minnesota, Public Health, Papillary