Developing a Registry for Thyroid Incidentalomas: Lessons Learned and the Path Forward

Abstract

Background: Incidentalomas are findings on an imaging test done for other reasons, for which there are no matching symptoms in the patient. They are common in the adrenal gland, pancreas, liver, and thyroid, among other sites. Incidentalomas are a problem because we have a limited understanding of their natural history: it is difficult to know how much of a threat they pose to individual patients. An observational registry that would allow a systematic study of thyroid incidentalomas could reveal their natural history and the effect of detection on patients' lives, as well as document the cost to the healthcare system. A registry would help to determine which incidentalomas could be monitored and which require action. Study design: A cohort study was conducted, with case identification via radiology imaging reports with follow-up through a minimum of one year post-identification. Results: In one year, >109,000 imaging studies were performed that might reveal an incidental thyroid finding (computed tomography scans of the neck or chest, magnetic resonance imaging of the neck, plain x-ray of the chest, non-thyroid directed ultrasound of the neck, positron emission tomography scan, or myocardial perfusion scan). A total of 125 patients were identified as having a thyroid nodule, with a <1% reporting rate among eligible imaging studies, much lower than other published estimates of incidental thyroid nodule prevalence on imaging. Of the 125 nodules, 46 had been previously identified (were not ''new''). Of the 79 patients with new nodules, more than half (44; 53%) were not notified of the finding. The approved study design allowed contact only with those who had been clearly notified of their thyroid nodule. Among those who could be reached, many did not recall the finding (6/15; 40%). Of those who did recall the finding, none self-identified it as an incidentaloma. Conclusions: There are serious logistical and ethical hurdles to developing observational registries of incidentalomas, as well as threats to data validity because incidentalomas are incompletely identified, reported, and acted upon. Solutions commonly used to optimize data quality for registries would increase reporting, but could potentially overwhelm the healthcare system and harm patients. A novel interventional design that is proposed here for future work may facilitate both study and amelioration of the problem.

[18F]FDG-PET/CT texture analysis in thyroid incidentalomas: preliminary results

“…Incidentalomas are findings on an imaging test performed for other reasons, for which there are no matching symptoms in the patient (Davies et al 2016 ). Published reports estimated the prevalence of thyroid incidentalomas on [ 18 F]FDG-PET images between 1.2% and 4.3% (Rigo et al 1996 ; Mitchell and Parangi 2005 ; Liu et al 2010 ).…”

“…Although the overall incidence of thyroid incidentalomas detected on PET imaging is low, the chance of malignancy among incidentalomas detected by [ 18 F]FDG is higher than incidental nodules discovered with other imaging modalities, with a chance for malignancy ranging from 14 to 59% (Gavriel et al 2015 ; Lee et al 2014 ; Demir et al 2016 ; Chun et al 2015 ; Are et al 2007 ; Pagano et al 2011 ; Cohen et al 2001 ; Nilsson et al 2011 ). Nonetheless, we have a limited understanding of the incidentaloma natural history (Davies et al 2016 ). Therefore, the differentiation between malignant and benign thyroid lesions is crucial to avoid unnecessary procedures, to improve the quality of life of patients, and to reduce healthcare costs.…”

Thyroid Incidentalomas in Hospitalized Patients With COVID-19: A Single-Center Retrospective Analysis

“…Previous studies revealed a wide range of prevalence of thyroid incidentalomas detected from CT scans, varying from <1% to 16% [ 4 , 5 , 27-29 ]. The higher prevalence is due to the dedicated imaging reviews of thyroid lesions [ 4 , 5 ], similar to our study.…”

“…The higher prevalence is due to the dedicated imaging reviews of thyroid lesions [ 4 , 5 ], similar to our study. In contrast, the larger database studies (∼100 000 imaging studies) identified thyroid incidentaloma with a <1% reported rate due to routine radiology reports in clinical practice [ 27 , 29 ]. The different rate of incidental detection of a thyroid nodule is 10% when comparing routine reports and dedicated reviews [ 29 ].…”

Thyroid Incidentalomas and the Overdiagnosis Conundrum

“…Only 0.4% of imaging studies of the head and neck resulted in a radiologist reporting an incidental thyroid nodule and only 0.03% of studies resulted in a confirmed diagnosis of thyroid cancer [9]. Interestingly a second study done at an institution in a completely different geographic region of the USA also reviewed roughly 100,000 imaging studies and found a thyroid incidentaloma reporting prevalence of 0.1% [10]. This is strikingly similar to our finding and is also in stark contrast to previous studies that estimate the number of thyroid incidentalomas on imaging studies to be between 6 and 33% [1,11,12].…”