Which risk stratification system is best for thyroid nodules?

By Amerigo Allegretto, AuntMinnie.com staff writer

February 9, 2023 -- The American College of Radiology (ACR) TI-RADS system is best for risk stratification of thyroid nodules found on ultrasound, according to a Korean study published February 8 in the American Journal of Roentgenology.

Researchers led by Dr. Do Hyun Kim, PhD, from the Catholic University of Korea in Seoul compared six different risk stratification systems in a meta-analysis that encompassed nearly 50,000 patients. They found that the ACR's Thyroid Imaging Reporting and Data System (TI-RADS) delivered the highest diagnostic performance.

"This comparative evaluation of risk stratification systems for thyroid nodules can inform decisions regarding system implementation, as well as aid future system updates," Kim and colleagues wrote.

Risk stratification systems are used to evaluate thyroid nodules on ultrasound. Different systems use varying approaches to classify levels of suspicion for malignancy. This can lead to variable performance.

To see which system was the best, Kim et al wanted to put these different risk stratification systems to the test in a meta-analysis that included 39 studies with 49,661 patients. All studies included had either fair (n = 17) or good (n = 22) image quality. The risk stratification systems analyzed in the study included the following:

• American Association of Clinical Endocrinologists/American College of Endocrinology/Associazione Medici Endocrinologi (AACE/ACE/AME)
• ACR TI-RADS
• American Thyroid Association (ATA)
• European Thyroid Association Thyroid Imaging Reporting and Data System (EU-TIRADS)
• Korean Thyroid Association/Korean Society of Thyroid Radiology Thyroid Imaging Reporting and Data System (K-TIRADS)
• Thyroid Imaging Reporting and Data System developed by Kwak et al. (Kwak TIRADS)

The authors used the surface under the cumulative ranking curve (SUCRA) to rank the systems in terms of sensitivity, specificity, and accuracy. Although all systems had varying advantages and disadvantages when it came to low-risk versus high-risk findings, they found that ACR TI-RADS had the highest overall metrics, followed by K-TIRADS.

Performance of thyroid ultrasound risk stratification systems
	EU-TIRADS	AACE/ACE/AME	ATA	Kwak TI-RADS	K-TIRADS	ACR TI-RADS
Sensitivity	5%	20%	39%	67%	81%	89%
Specificity	8%	27%	33%	62%	78%	93%
Accuracy	14%	66%	30%	50%	68%	72%

The researchers suggested that the higher performance of ACR TI-RADS and Kwak TIRADS are due to their being score-based systems and not pattern-based, the latter of which provide "less precise" estimates of malignancy risk.

ACR TI-RADS, however, includes an initial assignment of a varying number of points in multiple categories before calculating the sum of these points across categories to weigh certain findings. In addition, this method considers commonly encountered thyroid nodule characteristics, the study authors noted. Also, ACR TI-RADS recommends that follow-up ultrasound be performed in nodules smaller than the size cutoffs in the mildly, moderately, and highly suspicious categories.

In an accompanying editorial, Dr. Luyao Shen from Stanford University in California wrote that although ACR TI-RADS "can be cumbersome" to use compared with other guidelines, its structured system helps achieve consistency among readers. Shen also noted the system's larger size thresholds for biopsy recommendations, along with options for active surveillance for smaller nodules with suspicious features.

"Strong evidence supports ACR TI-RADS as the preferred system to risk stratify thyroid nodules," Shen wrote.

POCUS for UNCLEAR PULMONARY EMBOLISM

ABSTRACT

Point-of-care ultrasound (POCUS) has become a reliable and powerful tool working as a complement to the traditional physical examination. It has proven to be a reliable and reproducible method to a quicker and safer diagnosis, sometimes surpassing the diagnostic accuracy of more traditional techniques. We present two cases of pulmonary embolism (PE) with clinical presentations that suggested other diagnoses, prior to the performance of POCUS: a 60-year-old patient with nausea and vomiting and a 66-year-old female with a week-long progressive increase of shortness of breath and increased peripheral edema. In the reported cases, we aim to pinpoint the importance and usefulness of POCUS in the everyday evaluation of our patients, in multiple settings and by multiple specialty physicians, supported by its robust evidence-based background. It has proven to be a useful tool in evaluating in a fast and nonharmful way complementing more traditional techniques, which proves to be especially important regarding cases, like the ones we describe, when the correct diagnosis is not always clear to presentation. The use of multiorgan POCUS allows even in the most atypical presentations, the rise of suspicion of PE, leading to the necessary steps to a final diagnosis and management.
Keywords: Deep vein thrombosis, lung ultrasound, point-of-care ultrasound, pulmonary embolism

DISCUSSION 

Multiorgan POCUS has a robust evidence-based background. It is adopted by a variety of physicians in a lot of different settings,   allowing to a more efficient and quickly evaluation and management of our patients.[2,3] This way, it proves to be highly valuable as a complement to traditional examination tools, especially when it comes to cases where the clinical picture is unclear. Regarding PE, the range of presentations is wide,[4] frequently leading to misdiagnosis and otherwise preventable morbidity and death.[5] Atypical presenting symptoms of PE, such as syncope, recurrent fever,[6] bradycardia,[2] epigastric pain,[7] flank pain,[8] right upper quadrant and back pain,[9] and seizure,[10] are described in the literature despite their rarity. This leads to the need of a more cautious approach in patients with risk factors for PE despite their presentation.[4] The value of POCUS stands out in these cases, especially in a multiorgan approach.[2] Multiorgan POCUS including lung, venous compression, and focused cardiac ultrasound as a clinical adjunct can play a significant role in the diagnosis and management of PE. The presence of subpleural consolidations and focal B-lines is highly specific for focal interstitial syndrome (i.e., pneumonia, fibrosis, atelectasis, pulmonary infarction, neoplasia, etc.). Compression ultrasound is the mainstay of venous thrombosis diagnosis. Focused cardiac ultrasound may reveal evidence of right ventricle strain. Combining these examinations in a protocolized approach allows a quick but unrefutably precious look at the most important locations regarding PE.[2] POCUS is useful in the diagnosis of acute PE, either as a screening tool in patients with atypical presentation or as an aid before the confirmation by chest computed tomography in patients with high clinical suspicion, leading to the necessary steps to a final diagnosis and management. 

We have obtained informed consent from the patients.