USPSTF Releases Guidance on Screening for Thyroid Cancer

SUMMARY:

Screening for thyroid cancer includes the identification of nodules by neck palpation or ultrasound. Detection can also be incidental, for example at the time of carotid ultrasonography or chest CT. Nodules are mostly benign with only 7 to 9% considered cancerous on pathology and even then, malignant cells are usually well contained. Overall prognosis is excellent with less than 2% mortality at 5 years. Research indicates that even when thyroid carcinomas are detected early, mortality rates remain unchanged. Thus, patients may be exposed to surgeries and treatments that carry risk but may not result in benefit.

Based on the assessment of the current literature the task force concludes the following:

The USPSTF concludes with moderate certainty that screening for thyroid cancer in asymptomatic persons results in harms that outweigh the benefits. The USPSTF recommends against screening for thyroid cancer in asymptomatic adults (D recommendation).

Of note, this applies to asymptomatic, low risk adults. This guidance does not apply to individuals with the following:

Throat symptoms
- Hoarseness | pain | difficulty swallowing
Abnormal neck exam
- Lumps | swelling | asymmetry of the neck and other similar findings
Increased risk of thyroid cancer
- History of exposure to ionizing radiation (such as medical treatment or radiation fallout)
- Inherited genetic syndromes associated with thyroid cancer (e.g., familial adenomatous polyposis, family history of medullary thyroid cancer or MEN 2A or 2B syndrome)
- First-degree relative with a history of thyroid cancer

Patients with the above require an individualized management plan based on their clinical findings.

The accompanying editorial makes the point that more research is still warranted as the thyroid cancer incidence-based mortality is rising at approximately 1.1% per year. In addition, imaging techniques continue to improve. Therefore, ultrasound screening may become more effective in the future by incorporating specific sonographic characteristics.