The Epidemic of Thyroid Cancer in the United States: The Role of Endocrinologists and Ultrasounds

Abstract

Background: The incidence of thyroid cancer has increased at an alarming rate in both men and women in the United States. The etiology of this epidemic is unclear. We tested the hypothesis that a significant component of this epidemic is due to increased detection of occult disease. We examined whether the density of endocrinologists and general surgeons as well as employment of cervical ultrasonography were factors associated with this epidemic. Methods: Thyroid cancer incidence rates by states were obtained from the United States Cancer Statistics 1999-2009 reported by the National Program of Cancer Registries. The densities of endocrinologists and general surgeons and the employment of cervical ultrasonography were calculated on a statewide basis and correlated with the incidence of thyroid cancer. Results: Age-standardized incidence rates of thyroid cancer have increased in every state in the United States. Significant regional variations were noted, with the highest incidence rates in the northeast and the lowest in the south. The incidence rates were significantly correlated with the density of endocrinologists (r = 0.58, p < 0.0001 for males; r = 0.44, p = 0.0031 for females) and the employment of cervical ultrasonography (r = 0.40, p = 0.0091 for males; r = 0.36, p = 0.0197 for females). Both the density of endocrinologists and general surgeons and employment of cervical ultrasonography could explain 57% of the variability in state-level incidence for males and 49% for females. Conclusions: These data offer evidence to suggest that the epidemic of thyroid cancer is due to increased detection of a reservoir of previously occult disease. The increased detection of thyroid cancer results in therapeutic interventions including surgery and radioactive thyroid treatment that may be of limited benefit.

Disease Free Survival of Well Differentiated Thyroid Cancer: 20 years Experience at a tertiary care center in Lebanon

“…Thyroid cancer, the most common endocrine malignancy, has recently witnessed a steady increase in its incidence [1], due not only to medical surveillance and more sensitive diagnostic studies [2], but also to increased exposure to radiation from the increased use of imaging techniques such as computed tomography (CT) and other diagnostic x-rays [3,4]. Differentiated thyroid cancer (DTC) is the most common type and includes papillary (80%) and follicular (15%) cancers [5].…”

ENDOCRINE TUMOURS: Familial nonmedullary thyroid carcinoma is a more aggressive disease: a systematic review and meta-analysis

“…Thyroid cancer is the most common endocrine cancer and the incidence is increasing all over the world (1,2). It can be classified into two main groups depending on the cell origination: medullary thyroid carcinoma (MTC), which originates from the thyroid parafollicular calcitoninproducing C cells, and nonMTC (NMTC), which originates from follicular cells.…”

Thyroid Cancer ? South American Experience

“…Since the higher incidence may also be due to improved medical care surveillance and better diagnostic methods, these may also be the reasons for the rise observed in papillary micro carcinoma. The fact that the papillary micro carcinoma / papillary carcinoma ratio practically remains unchanged for men but changes for women, could potentially explain part of the increase observed in women [57,58].…”

“…Among the potential factors that impact the rise in papillary cancer in women, improved diagnostic techniques should be emphasized as a differential according to gender. Proof of that would be that the rise in thyroid cancer among women is mainly due to papillary cancer that includes a higher percentage of micro carcinomas as compared to males [58,59]. 4.…”