Israel Medical Association Journal

Background: The 2015 American Thyroid Association (ATA2015) and the American College of Radiology Thyroid Imaging and Reporting Data System (ACR TI-RADS) are two widely used thyroid sonographic systems.

Objectives: To compare the two systems for accuracy of cancer risk prediction.

Methods: Preoperative ultrasound images from 265 patients who underwent thyroidectomy at our hospital from January 2012 to March 2019 were retrospectively categorized by the ACR TI-RADS and ATA2015 systems. Diagnostic performances were compared.

Results: Of 238 nodules assessed, 115 were malignant. Malignancy risks for the five ACR TI-RADS categories were 0%, 7.5%, 11.4%, 59.6%, and 90.0%. Malignancy risks for the five ATA2015 categories were 0%, 6.8%, 17.0%, 55.5%, and 92.1%. The proportion of total nodules biopsied was higher with the ATA2015 system than the ACR TI-RADS system: 88.7% vs. 66.3%. Proportions of malignant nodules and benign nodules biopsied were higher with ATA2015 than with ACR TI-RADS: 93.3% vs. 87.8% and 84.4% vs. 46.3%, respectively. Specificity and sensitivity rates were 53.6% and 84.3%, respectively, for ACR TI-RADS, and 15.5% and 93.3%, respectively, for ATA2015. The two systems showed similarly accurate diagnostic performance (AUC > 0.88). False negative rates for ACR TI-RADS and ATA2015 were 15.6% and 6.6%, respectively. Rates of missed aggressive cancer were similar for the two systems: 3.4% and 3.7%, respectively.

Conclusion: ACR TI-RADS was superior to ATA2015 in specificity and avoiding unnecessary biopsies. ATA2015 yielded better sensitivity and a lower false negative rate. Identification of aggressive cancers was identical in the two systems

Background: Direct aspiration from suspected pathological tissue and rapid parathyroid hormone analysis may offer a reliable, cost effective alternative to currently used “gold standard” tests.

Objectives: To validate the accuracy of intraoperative measurements of parathyroid hormone levels in parathyroid adenomas.

Methods: A prospective study included 22 patients diagnosed with primary hyperparathyroidism who underwent parathyroidectomy due to an adenoma or hyperplasia. Aspirations of tissues extracted from three adjacent areas (the pathological parathyroid, thyroid, and muscle tissues) were sent for rapid parathyroid hormone analysis. The assay values of these tissue aspirates were compared to the results of the pathology report based on frozen section analysis and the final pathology report.

Results: All assay results were significantly higher for parathyroid tissue 16,800 to 1,097,986 pmol/L (median 26,600), than for either thyroid 1.7 to 415 pmol/L (median 6.5), P < 0.001, or muscle tissue 1.1 to 1230 pmol/L, (median 11.3), P < 0.001. All tissues showing high parathyroid assay values were also verified by pathology examinations: 7 had adenomas and 15 had a differential diagnosis of adenoma or hyperplasia. The frozen section identified all but one (false negative). Rapid intraoperative parathyroid levels > 1500 predicted parathyroid tissue with a 99% level of confidence, while levels between 1000 and 1500 predicted it with 95% confidence. The intraoperative parathyroid hormone assay showed > 70% decrease in 15/21 cases.

Conclusions: Rapid intraoperative parathyroid hormone analysis is a reliable and precise technique, equally accurate for frozen section analysis in predicting with high certainty intraoperative parathyroid tissue.