February 23, 2015
Thyroid cancer incidence has increased in individuals of all races and ethnicities, according to results of a retrospective review.
The greatest increase occurred among non-Hispanic whites, who now have a higher incidence of thyroid cancer than individuals of Asian/Pacific Islander descent, results showed.
“The increasing incidence of thyroid cancer across all racial and ethnic groups is an urgent public health concern, and various explanations have been suggested as the underlying cause,” David Goldenberg, MD, of the division of otolaryngology-head and neck surgery in the department of surgery at Penn State College of Medicine, and colleagues wrote. “Some studies have concluded that this increase in incidence is owing to an increase in the diagnosis of subclinical thyroid cancers, as opposed to an increase in the occurrence of thyroid cancer, because of an increased use of ultrasonography-guided fine-needle aspiration biopsies.”
Goldenberg and colleagues used the SEER database to determine the annual percentage change in thyroid cancer incidence from 1992 to 2010 among whites, blacks, Asians/Pacific Islanders and American Indian/Alaskan natives.
Historically, thyroid cancer has been the highest in Asians/Pacific Islanders. However, results from this study showed that whites had the highest increase in thyroid cancer incidence, whereas Asians/Pacific Islanders experienced the lowest increase.
During the study period, the average annual percentage change for thyroid cancer incidence was 5.3% (95% CI, 4.8-5.7). Whites experienced the largest increase (5.6% per year), followed by blacks (4.8% per year), American Indian/Alaskan natives (3.2% per year), and Asians/Pacific Islanders (2.3% per year).
Comparability testing revealed no significant difference in disease incidence between whites and blacks. However, the increase in thyroid cancer incidence among Asians/Pacific Islanders was significantly lower than incidence among whites and blacks (P < .05).
Stratification by ethnicity of the study population showed non-Hispanics experienced a larger increase in thyroid cancer incidence (5.5% per year) than Hispanics (3.3% per year).
“With the increased thyroid cancer incidence, a shift in incidence has occurred among different races and ethnicities,” Goldenberg and colleagues concluded. “Differences in access to care among races and ethnicities are not fully understood, but they may have a role in the shift in incidence. Other contributing factors include sex, exposure to environmental risks, lack or excess of dietary risks, and obesity. Further investigation of the various risk factors in different racial and ethnic groups is needed.” – by Lauren Frisby
Disclosure: The researchers report no relevant financial disclosures.