While the incidence of many head and neck cancers in the United States is decreasing, a number of registries have reported that the incidence of thyroid cancer is increasing. Some investigators have attributed the increase to environmental radiation, while others believe it could be from increased diagnostic scrutiny, according to background information in the article.
Although some thyroid cancers can spread and cause death, thyroid cancer has also been recognized to exist in a subclinical (before symptoms) form. Autopsy studies have revealed that many individuals not known to have thyroid cancer during their lifetime had thyroid cancer, particularly papillary cancers. As diagnostic techniques for thyroid cancer have become more sensitive, such as with the advent of ultrasound and fine-needle aspiration, it has become possible to detect this subclinical disease. Thus, while increasing incidence of thyroid cancer might reflect an increase in the true occurrence of disease, it might also reflect increased diagnostic scrutiny or changes in diagnostic criteria. Examination of the reasons underlying an increase in the incidence of thyroid cancer is important, because if there is an increase in the true occurrence of disease, efforts should be made to address its cause and aid those at greatest risk of developing the disease.
Louise Davies, M.D., M.S., and H. Gilbert Welch, M.D., M.P.H., of the Department of Veterans Affairs Medical Center, White River Junction, Vt., examined the trends in thyroid cancer incidence, histology, size distribution, and death in the U.S. to determine whether the patterns suggest a true change in thyroid cancer incidence or
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Contact: Ansem Beach
802-295-9363
JAMA and Archives Journals
9-May-2006