Many thyroid cancers are discovered in patients without thyroid-referable symptoms, according to an international study published in JAMA Otolaryngology-Head & Neck Surgery.1
Approximately half of the thyroid cancers in this study were detected in patients who underwent surgery without thyroid-referable symptoms. This finding supports the idea that the observed increase in thyroid cancer incidence is due to subclinical disease detection, according to researchers.
The researchers noted that it hasn’t been clear whether the rising incidence of thyroid cancer is due to subclinical disease detection or a true increase in thyroid cancer incidence.
To gain some insight, the researchers evaluated data from 1328 patients who underwent thyroid surgery in 2019 at 16 institutions in Canada, Denmark, South Africa, and the United States. At baseline, the patients’ mean age was 52 years, and 75% of patients were women.
A total of 613 patients had thyroid cancer. Most (84%) had papillary thyroid cancer, 10% had follicular, 5% had medullary, and 1% had poorly differentiated or anaplastic thyroid cancer.
About half of these patients (310/613) underwent surgery without thyroid-referable symptoms, 30% had thyroid symptoms, 7% had endocrine conditions, and 13% were under surveillance.
The asymptomatic thyroid cancer cases were identified via incidental radiologic findings (24%), clinician-initiated screening (16%), diagnostic cascade (8%), or patient-requested screening (2%).
Larger tumor size was associated with symptomatic thyroid cancer. The mean tumor size was 3.2 cm in patients with symptomatic disease and 2.1 cm in patients with asymptomatic disease. Patients in the symptomatic group were more likely to have tumors larger than 4 cm (29% vs 9%).
“[This study] confirms that many patients who undergo thyroid surgery initially present as asymptomatic,” authors of a related editorial wrote.2 “Despite a lack of symptoms, patients are found to have thyroid pathology, most often thyroid nodules, which begins a process that often ends with surgery and the diagnosis [of] thyroid cancer.”
“This aggressive evaluation and treatment cascade of asymptomatic patients is likely contributing to the overdiagnosis and overtreatment of thyroid cancer,” the editorialists continued. “Future efforts are required to shift toward a less aggressive process, including preventing inappropriate evaluation with screening thyroid ultrasonography and increased implementation of active surveillance protocols of small PTCs [papillary thyroid carcinomas], to avoid unnecessary and inappropriate thyroid surgery.”
Disclosures: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.
1. Sajisevi M, Caulley L, Eskander A, et al. Evaluating the rising incidence of thyroid cancer and thyroid nodule detection modes. A multinational, multi-institutional analysis. JAMA Otolaryngol Head Neck Surg. Published online July 14, 2022. doi:10.1001/jamaoto.2022.1743
2. Drake T, Caicedo-Granados E. Most thyroid surgeries start with an asymptomatic patient. JAMA Otolaryngol Head Neck Surg. Published online July 14, 2022. doi:10.1001/jamaoto.2022.1744