The Usefulness of the Thyroid Imaging Reporting and Data System in Determining Thyroid Malignancy

Evaluating the Diagnostic Role of ACR-TIRADS and Bethesda Classifications in Thyroid Nodules Highlighted by Cyto-Histopathological Studies

OBJECTIVE

To evaluate the accuracy of thyroid imaging reporting and data system (ACR-TIRADS) and the Bethesda system for reporting cytopathology (TBSRCP) classifications for identifying or ruling out thyroid malignancy in relation to the gold standard (post-surgical pathology).

METHODS

This cross-sectional study included 573 patients with single or multiple thyroid nodules. Patients were evaluated using the TIRADS and the TBSRCP classification. The data from a cohort of patients who underwent surgery (77/573, 13.4%) were correlated with post-operative pathology and the relevant clinical features of the patients.

RESULTS

Of 573 patients, 545 (95.1%) were euthyroid, 24 (4.1%) were hypothyroid, and 4 (0.8%) were hyperthyroid; 419 (73.1%) had benign nodules (Bethesda II), 115 (20.1%) had intermediate (Bethesda III, IV), and 39 (6.8%) had Bethesda V and VI nodules. Four-hundred twenty (73.3%) patients were categorized as TIRADS 2,3, and 153 (26.7%) were categorized as TIRADS 4,5. The Bethesda and TIRADS classifications concorded significantly in thyroid nodule diagnosis (K=14.9%, P<0.001).Thyroid malignancy was significantly associated with microcalcification and interrupted halo, while benign nodules were significantly associated with macrocalcification and complete halo type (P=0.041, P=0.005, respectively). The TBSRCP could significantly detect malignant thyroid nodules with a sensitivity, specificity, PPV, and NPV of 64.1%, 98.1%, 85.0%, and 94.1%, respectively (K=88.2%, P<0.001), while the respective values for the TIRADS classification were 63.5%, 76.0%, 84.6%, and 50.0% (K=34.8%, P=0.001).

CONCLUSION

The TIRADS and TBSRCP are essential primary steps for evaluating thyroid nodules and both are complimentary. Hence, each patient with thyroid nodules should be evaluated by both approaches before opting for surgery. Highly suspicious TIRADS categories TR4 and TR5 need further evaluation by fine needle aspiration cytology.

Agreement Between Ti-RADS Classification and Bethesda Cytopathological Findings from Thyroid Nodules in Young Adults

INTRODUCTION

Thyroid nodules are common in young adults. We sought to compare the sonographic characteristics (thyroid imaging reporting and data system [Ti-RADS] classification) with the reported cytological results (Bethesda categories) from thyroid nodules in young recruits and examine the efficiency of our unique multidisciplinary clinic.

MATERIALS AND METHODS

In this retrospective cohort, we identified young recruits (18-25 years) who underwent needle biopsies for asymptomatic thyroid nodule(s), with cytology reports of Bethesda categories II-V, performed in our "Rapid Diagnostic Service" at a large Israeli Defense Forces Medical Corps healthcare facility, between 2013 and 2018. We studied the concordance rates between their Ti-RADS and Bethesda grades, and the preoperative Bethesda grades accuracy versus final pathology results, and the time period needed for their thyroid nodules workup.

RESULTS

A total of 81 patients were included who contributed 91 nodules. A fair agreement was found between the Ti-RADS classifications and the Bethesda grades (Cohen's κ = 0.238) that was more noticeable in males than in females. The agreement rate was 87.5% in males (21 of 24), but only 77.6% in females (59 of 67) [P = .029]. Of the 5 operated benign cases, all had low Ti-RADS, and 2 had low Bethesda. Of the 8 operated malignant cases, 6 had high Ti-RADS, and 5 had high Bethesda. On average, 37.64 days elapsed between the first visit to the ultrasound study, and 24.2 days elapsed until biopsy was performed.

CONCLUSIONS

Despite an overall fair agreement between the sonographic features and cytological findings in young adults, we recommend a more aggressive approach and repeated biopsies despite reported benign pathology, because of a high false-negative rate.