Avoidance of unnecessary fine-needle aspiration with the use of the Thyroid Imaging Reporting Data System classification and strain elastography based on The Bethesda System for Reporting Thyroid Cytopathology

The clinical significance of the American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TI-RADS) category 5 thyroid nodules: Not as risky as we think?

BACKGROUND

Although the prevalence of thyroid nodules is high, few prove to be malignant. Based on sonographic features, the American College of Radiology Thyroid Imaging Reporting and Data System categorizes malignancy risk of thyroid nodules with associated management recommendations for each category level. Malignancy rates among nodules with a highly suspicious Thyroid Imaging Reporting and Data System category 5 warrant examination in the context of additional risk stratification tools, including cytopathology and molecular testing.

METHODS

All patients who underwent fine-needle aspiration biopsy for Thyroid Imaging Reporting and Data System category 5 nodules from January 2018 to September 2021 in a large integrated academic health system were reviewed. Using the Bethesda System for Reporting Thyroid Cytopathology, categories V and VI were set as malignant. Molecular testing (ThyroSeq version 3; Rye Brook, NY) yielding ≥50% risk of malignancy was deemed positive and correlated with surgical pathology.

RESULTS

A total of 496 Thyroid Imaging Reporting and Data System category 5 nodules were identified. On fine-needle aspiration cytopathology, 61 (12.3%) were malignant. The breakdown included Bethesda System for Reporting Thyroid Cytopathology I, 15 (3%); II, 362 (73%); III, 52 (10.5%); IV, 5 (1%); V, 6 (1.3%); and VI, 55 (11.1%). Of Bethesda System for Reporting Thyroid Cytopathology III/IV nodules with molecular testing (n = 53), 24.5% yielded positive results. In total, 42 (8.5%) nodules underwent surgical resection, most of which were Bethesda System for Reporting Thyroid Cytopathology VI (n = 26, 61.9%). Of excised nodules, 33 (78.6%) nodules were malignant, 6 (14.3%) benign, and 3 (7.1%) noninvasive follicular thyroid neoplasm with papillary-like nuclear features. All Thyroid Imaging Reporting and Data System category 5 nodules with malignant cytology (Bethesda System for Reporting Thyroid Cytopathology V/VI) that underwent surgery were malignant on histopathology. On average, the total Thyroid Imaging Reporting and Data System points were higher in malignant nodules compared with benign (9.3 vs 7.3; P = .015). Moreover, benign nodules more frequently received Thyroid Imaging Reporting and Data System points when the radiologist was unable to determine composition or echogenicity (33% vs 3% among malignant nodules; P = .01).

CONCLUSION

Thyroid Imaging Reporting and Data System category 5 designation in thyroid nodules is associated with a lower risk of malignancy than previously reported. Benign and malignant nodules with Thyroid Imaging Reporting and Data System category 5 designation have discrepancies in certain Thyroid Imaging Reporting and Data System characteristics and individual points assigned, which may offer an opportunity for quality improvement and standardization measures in ultrasound reporting practices.

Comparative Study of ACR TI-RADS and ATA 2015 for Ultrasound Risk Stratification of Thyroid Nodules

OBJECTIVE

To study the adoption rate of the American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) scoring system over a 3-year period in a community setting and compare its performance with that of the American Thyroid Association 2015 (ATA 2015) ultrasound risk scoring system.

STUDY DESIGN

Case series with prospective data collection and retrospective chart review.

SETTING

Large community-based practice with multiple satellite offices and a dedicated thyroid ultrasound clinic.

METHODS

All patients referred to the thyroid clinic between January 2018 and December 2020 for ultrasound-guided fine-needle biopsy were assigned an ATA 2015 risk score in a prospective manner immediately prior to biopsy. ACR TI-RADS scores were recorded through retrospective chart review of the radiologist report. Performance of the 2 systems was compared with cytology as the gold standard.

RESULTS

A total of 949 nodules underwent biopsy, of which 236 had available data for both scoring systems. There was a 33.8% increase in adoption of the ACR TI-RADS over the 3-year study period. The ATA 2015 guidelines yielded sensitivity and specificity of 81.6% and 54.5%, respectively, as opposed to 73.7% and 27.0% for the ACR TI-RADS.

CONCLUSION

In our community, there has been a gradual increase in adoption of the ACR TI-RADS, although the ATA 2015 risk scoring system has performed better.

Systems of Risk Stratification of Malignancy by Ultrasound of Thyroid Nodules

Thyroid nodules (TN) are more frequently identified with the use of thyroid ultrasonography, and they have a low risk of malignancy. Ultrasonographic features have been established that increase the probability of being faced with thyroid carcinoma; however, individually, these characteristics do not perform adequately in the diagnosis of malignancy, limiting their usefulness when indicating cytological studies by means of fine-needle aspiration (FNC). This situation motivated the development of risk stratification systems for thyroid nodules, which unified their ultrasound characteristics, with the aim of establishing risk categories, standardizing the preparation of reports, and providing the clinician with useful tools to define the surveillance option or form invasive studies.

The objective of this review is to compare the different systems developed by some scientific societies for the stratification of thyroid nodules, with respect to their predictive capacities for malignancy, their operational characteristics for diagnosis, and, to suggest recommendations for the implementation of these systems, placing emphasis on those with the best ability to reduce the performance of unnecessary invasive studies and to guide decision-making in the face of undetermined cytological results.

Ultrasonography and the American Thyroid Association Ultrasound-Based Risk Stratification Tool: Utility in Pediatric and Adolescent Thyroid Nodules

BACKGROUND

Pediatric thyroid nodules are more likely to be malignant compared to those in adults and may have different concerning ultrasound (US) features. Recent adult guidelines stratify malignancy risk by US features. Our aim is to (1) describe and confirm US features that predict pediatric malignancy, and (2) apply the Adult American Thyroid Association (ATA) Risk Stratification Guidelines to a large pediatric cohort.

METHODS

We identified 112 children with 145 thyroid nodules from 1996 to 2015. Two blinded pediatric radiologists independently read all US images, described multiple features, and reported their overall impression: benign, indeterminate, or malignant. Each nodule was assigned an ATA risk stratification category. Radiologists' impressions and ATA risk stratification were compared to histology and cytology results.

RESULTS

Multiple US features including a solid composition, presence of microcalcifications, irregular margins, increased blood flow, and hypoechogenicity were associated with increased odds of malignancy. ATA risk stratification correlated with the radiologists' overall impression (p < 0.001). The sensitivity for detecting malignancy was comparable between both ATA stratification (91%) and the radiologists' overall impression (90%). The specificity of the radiologists' malignant overall impression (80%) was better compared to the ATA high risk stratification (54%).

CONCLUSIONS

At our institution, pediatric radiologists' overall impressions had similar sensitivity but better specificity for detecting malignancy than the ATA risk stratification tool by our convention. However, neither US-based methods perfectly discriminated benign from malignant nodules, supporting the continued need for fine needle aspiration for suspicious nodules. Further work is needed to develop an US-based scoring system specific to pediatric patients.

Diagnostic accuracy of the McGill thyroid nodule score in paediatric patients

INTRODUCTION

Thyroid cancer is the most common paediatric endocrine cancer; accurate diagnosis and prompt management of paediatric thyroid nodules is critical. The McGill Thyroid Nodule Score (MTNS), based upon clinical, ultrasound (US) and cytology criteria, has recently been modified and studied in a pilot paediatric group with good results. We aim to describe the diagnostic accuracy of the paediatric modified MTNS (PMTNS) in a large paediatric cohort.

METHODS

We utilized an established retrospective cohort between 1996 and 2015 of 99 patients ≤21 years old with 131 thyroid nodules. Two experienced paediatric radiologists, blinded to pathology and radiology reports, reviewed US features. We abstracted cytology, histology and laboratory results, assigning each nodule a PMTNS. PMTNS performance was compared to FNA and histology.

RESULTS

Approximately 33% of nodules were malignant. The cohort was predominantly adolescent (mean age 15.4 ± 3.8 years). The average PMTNS for malignant and benign nodules, based on final histology, was 12.7 ± 4.3 and 1.7 ± 2.9, respectively. A PMTNS ≥8 resulted in a 93.2% sensitivity and 93.1% specificity for detecting malignancy, while a PMTNS ≥9 resulted in a 90.9% sensitivity and 96.6% specificity. However, Bethesda cytology category ≥4 independently had a 97.7% sensitivity and 94.0% specificity for detecting malignancy. The PMTNS had diminishing diagnostic accuracy in younger children compared with older children.

CONCLUSION

Paediatric modified McGill Thyroid Nodule Score predicts malignancy, perhaps due to the score's emphasis on cytology results; however, the score is less accurate in younger patients. While cytology results remain reliable, further work is needed to develop a non-invasive scoring system to predict malignancy in children.

Feasibility of 2-D ultrasound shear wave elastography of fetal lungs in case of threatened preterm labour: a study protocol

INTRODUCTION

2-D ultrasound shear wave elastography (SWE) could be considered as a new noninvasive tool for monitoring fetal lung development based on evaluation of mechanical properties during pregnancy. Interesting results are available concerning the use of SWE on developing organs, especially on premature infants and animal models. The main objective in this study is to evaluate the feasibility of 2-D SWE in human fetal lungs between 24 and 34 weeks of gestation (WG). The secondary objective is to modellise fetal lung-to-liver elastography ratio (LLE ratio) and to assess variations between normal lung and lung surfactant-enriched after a corticosteroids course indicated for a threatened preterm labour (TPL).

METHODS/DESIGN

A prospective case-control study will be performed between 24 and 34 WG. Fetal lungs and liver will be explored by SWE into two groups: fetuses of women with an uncomplicated pregnancy (control group) and fetuses of women with a TPL requiring administration of corticosteroids (cases group). LLE ratio will be defined as the value of the lung elasticity divided by the value of the liver elasticity.Primary judgement criterion is the value of elasticity modulus expressed in kilopascal. Lungs and liver will be explored through three measurements to define the most reproducible regions with the lowest intra- and inter-observer variability. Feasibility will be evaluated by assessing the number of examinations performed and the number of examinations with interpretable results. Intra- and inter-observer reproducibility will be evaluated by means of the intra-class correlation coefficient.

ETHICS AND DISSEMINATION

Approval of the study protocol was obtained from the human ethical research committee (Comité de Protection des Personnes EST II, process number 15/494) and the French National Agency for Medicines and Health Products Safety (process number 2015-A01575-44). All participants will sign a statement of informed consent.

TRIAL REGISTRATION NUMBER

NCT02870608; Recruiting.