HIGH PREVALENCE OF AGENT ORANGE EXPOSURE AMONG THYROID CANCER PATIENTS IN THE NATIONAL VA HEALTHCARE SYSTEM

Thyroid cancer is the most common endocrine malignancy and the most rapidly increasing cancer in the U.S. Little is known regarding the epidemiology and characteristics of patients with thyroid cancer within the national Veterans Health Administration (VHA) integrated healthcare system. The aim of this study was to further understand the characteristics of thyroid cancer patients in the VHA population, particularly in relation to Agent Orange exposure.

This is a descriptive analysis of the VA (Veterans Affairs) Corporate Data Warehouse database from all U.S. VHA healthcare sites from October1, 1999, to December 31, 2013. Information was extracted for all thyroid cancer patients based on International Classification of Diseases-ninth revision diagnosis codes; histologic subtypes of thyroid cancer were not available.

There were 19,592 patients (86% men, 76% white, 58% married, 42% Vietnam-era Veteran) in the VHA system with a diagnosis of thyroid cancer within this 14-year study period. The gender-stratified prevalence rates of thyroid cancer among the Veteran population during the study period were 1:1,114 (women) and 1:1,023 (men), which were lower for women but similar for men, when compared to the U.S. general population in 2011 (1:350 for women and 1:1,219 for men). There was a significantly higher proportion of self-reported Agent Orange exposure among thyroid cancer patients (10.0%), compared to the general VHA population (6.2%) (P<.0001).

Thyroid cancer patients, in this sample, have a higher prevalence of self-reported Agent Orange exposure compared to the overall national VA patient population.

T4 = thyroxine TCDD = 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin TSH = thyroid-stimulating hormone VA = Veterans Affairs VHA = Veterans Health Administration.