(HealthDay News) — The overall incidence of thyroid cancer increased by 3.6 percent annually from 1974 to 2013, according to a study published online March 31 in the Journal of the American Medical Association.
Hyeyeun Lim, Ph.D., from the National Cancer Institute in Bethesda, Md., and colleagues used data from the Surveillance, Epidemiology, and End Results-9 (SEER-9) cancer registry program to examine trends in thyroid cancer incidence and incidence-based mortality rates. Data were included for 77,276 patients diagnosed with thyroid cancer from 1974 to 2013.
The researchers found that papillary thyroid cancer was the most common histologic type (64,625 cases). From 1994 to 2013 there were 2,371 thyroid cancer deaths. There was an increase in the incidence of thyroid cancer, on average by 3.6 percent per year during 1974 to 2013, mainly due to increases in papillary thyroid cancer (annual percentage change, 4.4 percent). The incidence of papillary thyroid cancer increased for all SEER stages at diagnosis (4.6, 4.3, 2.4, and 1.8 percent per year for localized, regional, distant, and unknown, respectively). Incidence-based mortality increased 1.1 percent per year from 1994 to 2013 overall and by 2.9 percent per year for SEER distant stage papillary thyroid cancer.
“These findings are consistent with a true increase in the occurrence of thyroid cancer in the United States,” the authors write.
One author disclosed being on the Data Monitoring Committee of the Medullary Thyroid Cancer Consortium Registry, which is sponsored by pharmaceutical companies.