The Acceleration in Papillary Thyroid Cancer Incidence Rates is Similar Among Racial and Ethnic Groups in the United States

Reports of similar age-specific incidence rates and a female-to-male gender disparity by racial/ethnic groups suggests that further consideration of race-specific patterns may confer insight into the possible causes of thyroid cancer or explanations for the increase in incidence. We used the National Cancer Institute's (NCIs) surveillance, epidemiology, and end results (SEER) program and Joinpoint Regression for cases diagnosed during 1992-2009 to investigate trends and rates of acceleration for papillary thyroid cancer by gender and race/ethnicity. We determined the annual percent change (APC) and found a yearly increase of 7.0 % for papillary thyroid cancer for the most recent APC trend, with an APC of 6.3 and 7.1 % for white males and females, respectively; an APC of 4.3 and 8.4 % for black males and females, respectively; an APC of 4.2 and 6.7 % for Hispanic males and females, respectively; and an APC of 3.4 and 6.4 % in Asian/PI males and females, respectively. The APC projections show the rates of papillary thyroid cancer rising in males, but the patterns are more dramatic in females, with rates of papillary thyroid cancer in females surpassing rates of common cancers and becoming the third most common cancer in women of all ages by 2019. Although the lowest rates of thyroid cancer are observed in blacks, the greatest rate of acceleration is occurring in black females. Our data also show that the rate of papillary thyroid cancer will continue to surpass rates of ovarian cancer, and in white women: it is projected to be more incident than colorectal cancer as well; and in Hispanic and Asian/Pacific Islander women, rates of papillary thyroid cancer are projected to be higher than lung, colorectal, and ovarian cancers in the near future.