ContextIncreasing cancer incidence is typically interpreted as an increase in the true occurrence of disease but may also reflect changing pathological criteria or increased diagnostic scrutiny. Changes in the diagnostic approach to thyroid nodules may have resulted in an increase in the apparent incidence of thyroid cancer.ObjectiveTo examine trends in thyroid cancer incidence, histology, size distribution, and mortality in the United States.MethodsRetrospective cohort evaluation of patients with thyroid cancer, 1973-2002, using the Surveillance, Epidemiology, and End Results (SEER) program and data on thyroid cancer mortality from the National Vital Statistics System.Main Outcome MeasuresThyroid cancer incidence, histology, size distribution, and mortality.ResultsThe incidence of thyroid cancer increased from 3.6 per 100 000 in 1973 to 8.7 per 100 000 in 2002—a 2.4-fold increase (95% confidence interval [CI], 2.2-2.6; P .20 for trend). Virtually the entire increase is attributable to an increase in incidence of papillary thyroid cancer, which increased from 2.7 to 7.7 per 100 000—a 2.9-fold increase (95% CI, 2.6-3.2; P<.001 for trend). Between 1988 (the first year SEER collected data on tumor size) and 2002, 49% (95% CI, 47%-51%) of the increase consisted of cancers measuring 1 cm or smaller; 87% (95% CI, 85%-89%) consisted of cancers measuring 2 cm or smaller. Mortality from thyroid cancer was stable between 1973 and 2002 (approximately 0.5 deaths per 100 000).ConclusionsThe increasing incidence of thyroid cancer in the United States is predominantly due to the increased detection of small papillary cancers. These trends, combined with the known existence of a substantial reservoir of subclinical cancer and stable overall mortality, suggest that increasing incidence reflects increased detection of subclinical disease, not an increase in the true occurrence of thyroid cancer.

https://jamanetwork.com/journals/jama/articlepdf/202835/JOC60052.pdf

Increasing incidence of thyroid cancer in the United States, 1973-2002.

NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines

Ductal carcinoma in situ (DCIS) of the breast represents a heterogeneous group of neoplastic lesions in the breast ducts. The goal for management of DCIS is to prevent the development of invasive breast cancer. This manuscript focuses on the NCCN Guidelines Panel recommendations for the workup, primary treatment, risk reduction strategies, and surveillance specific to DCIS.

https://www.unitypoint.org/desmoines/filesimages/Cancer%20Education/Oncology%20Nursing%20Conference/2015/2014%20NCCN%20Clin%20Pract%20Guidelines%20Male%20Sex%20Dysf.pdf

Clinical practice guidelines in oncology

The aim of the study was to correlate the sonographic [ultrasound (US)] and color-Doppler (CFD) findings with the results of US-guided fine needle aspiration biopsy (FNA) and of pathologic staging of resected carcinomas to establish: 1) the relative importance of US features as risk factors of malignancy; and 2) a cost-effective management of nonpalpable thyroid nodules. Four hundred ninety-four consecutive patients with nonpalpable thyroid nodules (8–15 mm) were evaluated by US, CFD, and US-FNA. Ninety-two patients with inadequate cytology were excluded from the study. All patients with suspicious or malignant cytology underwent surgery, whereas subjects with benign cytology had clinical and US control 6 months later. Thyroid malignancies were observed in 18 of 195 (9.2%) solitary thyroid nodules and in 13 of 207 (6.3%) multinodular goiters. Cancer prevalence was similar in nodules greater or smaller than 10 mm (9.1 vs. 7.0%). Extracapsular growth (pT4) was present in 35.5%, and nodal involvement in 19.4...

/pdf/risk-of-malignancy-in-nonpalpable-thyroid-nodules-predictive-kh93bwpgur.pdf

Risk of malignancy in nonpalpable thyroid nodules: predictive value of ultrasound and color-Doppler features.

Importance We have previously reported on a doubling of thyroid cancer incidence—largely due to the detection of small papillary cancers. Because they are commonly found in people who have died of other causes, and because thyroid cancer mortality had been stable, we argued that the increased incidence represented overdiagnosis. Objective To determine whether thyroid cancer incidence has stabilized. Design Analysis of secular trends in patients diagnosed with thyroid cancer, 1975 to 2009, using the Surveillance, Epidemiology, and End Results (SEER) program and thyroid cancer mortality from the National Vital Statistics System. Setting Nine SEER areas (SEER 9): Atlanta, Georgia; Connecticut; Detroit, Michigan; Hawaii; Iowa; New Mexico; San Francisco–Oakland, California; Seattle–Puget Sound, Washington; and Utah. Participants Men and women older than 18 years diagnosed as having a thyroid cancer between 1975 and 2009 who lived in the SEER 9 areas. Interventions None. Main Outcomes and Measures Thyroid cancer incidence, histologic type, tumor size, and patient mortality. Results Since 1975, the incidence of thyroid cancer has now nearly tripled, from 4.9 to 14.3 per 100 000 individuals (absolute increase, 9.4 per 100 000; relative rate [RR], 2.9; 95% CI, 2.7-3.1). Virtually the entire increase was attributable to papillary thyroid cancer: from 3.4 to 12.5 per 100 000 (absolute increase, 9.1 per 100 000; RR, 3.7; 95% CI, 3.4-4.0). The absolute increase in thyroid cancer in women (from 6.5 to 21.4 = 14.9 per 100 000 women) was almost 4 times greater than that of men (from 3.1 to 6.9 = 3.8 per 100 000 men). The mortality rate from thyroid cancer was stable between 1975 and 2009 (approximately 0.5 deaths per 100 000). Conclusions and Relevance There is an ongoing epidemic of thyroid cancer in the United States. The epidemiology of the increased incidence, however, suggests that it is not an epidemic of disease but rather an epidemic of diagnosis. The problem is particularly acute for women, who have lower autopsy prevalence of thyroid cancer than men but higher cancer detection rates by a 3:1 ratio.

https://jamanetwork.com/journals/jamaotolaryngology/articlepdf/1833060/ooi140001.pdf

Current Thyroid Cancer Trends in the United States

Background: Thyroid nodules are commonly identified on autopsy examination. There are relatively few descriptions, however, of the frequency with which thyroid nodules are encountered incidentally during the course of other investigations. Method: Prospective study to examine the prevalence of thyroid nodules in asymptomatic North American subjects, with palpation findings compared with findings on high-resolution ultrasonography. Results: Palpable nodules were identified in 21 (21%) of 100 subjects, with nine solitary nodules (9%) and 12 multiple nodules (12%). In comparison, only 33 subjects were found to be free of any nodules by ultrasonography. Of the 67 subjects with abnormal ultrasound findings, 22 had solitary nodules (22%) and 45 had multiple nodules (45%). The prevalence of nodules was greater in women (72%) than in men (41%) ( P Conclusions: The data indicate that thyroid abnormalities are very common incidental findings, emphasizing the need for a conservative approach when such lesions are encountered incidentally. (Arch Intern Med. 1994;154:1838-1840)

https://jamanetwork.com/HttpHandlers/ArticlePdfHandler.ashx?journal=INTEMED&articleId=619228&pdfFileName=archinte_154_16_010.pdf

Delver R. Cain

Papers

Thyroid Incidentalomas: Prevalence by Palpation and Ultrasonography