Subcategorization of intermediate suspicion thyroid nodules based on suspicious ultrasonographic findings

Malignant risk of thyroid nodules with isolated macrocalcifications - A study based on surgery results

OBJECTIVE

To determine the malignancy risk of thyroid nodules with Isolated Macrocalcifications (IMC) based on surgical results and evaluate the postoperative risk of malignant nodules with IMC.

METHODS

A total of 46 thyroid nodules with IMC were enrolled from 3680 consecutive patients who underwent thyroidectomy between August 2018 and September 2023. The malignancy risk of IMC nodules, postoperative risk of malignant nodules, and whether the ultrasonic features of IMC (smooth, lobulated, or focal disruption of the anterior margin) were associated with malignancy were investigated. The nodules were further divided into three groups (group A, maximum diameter < 10 mm; group B, maximum diameter of 10‒14 mm and group C, maximum diameter ≥ 15 mm). Differences in malignancy and Lymph Node Metastasis (LNM) risks were also evaluated among the three groups.

RESULTS

The malignancy risk of the IMC nodules was 30.43% (14/46). Four patients developed LNM. Eight nodules were staged as T1aN0M0 and low-risk, whereas six nodules were staged as T1bN1aM0 and intermediate-risk. Focal disruption of the anterior margin of IMC was significantly associated with malignancy. Malignant and LNM risk showed no differences among nodules with different sizes.

CONCLUSIONS

IMC nodules with different sizes had a lower intermediate risk of malignancy and exhibited the same aggressive behavior. The cutoff value of these nodules for further Fine Needle Aspiration (FNA) warranted further investigation. Interruption of IMC was more often seen in malignant nodules, and more attention should be paid to these nodules.

Thermal ablation for Bethesda III and IV thyroid nodules: current diagnosis and management

The diagnosis and management of Bethesda III and IV thyroid nodules remain clinical dilemmas. Current guidelines from academic societies suggest active surveillance or diagnostic lobectomy. However, the extent of surgery is often inappropriate, and a considerable percentage of patients experience under- or over-treatment. Thermal ablation has gained popularity as a safe and effective alternative treatment option for benign thyroid nodules. This review explores the feasibility of thermal ablation for Bethesda III or IV thyroid nodules, aiming to preserve the thyroid organ and avoid unnecessary surgery. It emphasizes individualized management, the need to consider factors including malignancy risk, clinical characteristics, and sonographic features, and the importance of supplemental tests such as repeat fine needle aspiration cytology, core needle biopsy, molecular testing, and radioisotope imaging.

Evolutionary analysis of indeterminate cytology and risk of malignancy in a thyroid nodule unit

OBJECTIVE

The objective of this study was to analyze the evolution in the diagnosis and management of indeterminate thyroid nodules over three time periods.

METHODS

3020 patients with thyroid nodules underwent cytological evaluation during three periods (2006-2008, 2012-2014, 2017-2019). Distribution of diagnostic cytologies, risk of malignancy, diagnostic performance indices of FNA, and cytologic-histologic correlation in indeterminate cytologies were analyzed.

RESULTS

only 2.2% of cytology tests were insufficient for a diagnosis. 86.9% cytologies were benign, 1.7% malignant, and 11.4% indeterminate. Indeterminate cytology rates were 15.9% (2006-2008), 10.1% (2012-2014), and 10% (2017-2019). Surgery was performed in 13% of benign cytology, result-ing in malignant histology in 2.7%. All malignant and suspicious cytologies underwent surgery: malig-nancy confirmed in 98% and 77% of cases, respectively. All 'indeterminate with atypia' cytologies (2006-2008) and Bethesda IV (2012-2014; 2017-2019) un-derwent surgery, with malignancy confirmed in 19.6%, 43.8%, and 25.7%, respectively. In the 'inde-terminate without atypia' category (2006-2008) and Bethesda III (2012-2014; 2017-2019), diagnostic surgery was performed in 57.7%, 78.6%, and 59.4%, respectively, with malignancy confirmed in 3.3%, 20.5%, and 31.6%. The FNA sensitivity was 91.6% with a negative predictive value greater than 96% in all periods. The specificity exceeded 75% in the last two periods.

CONCLUSION

Bethesda system reduces indeterminate cytologies and improves the accuracy of FNA diagnosis. We reported a higher proportion of malignancy than expected in Bethesda III, underscoring the importance of having institution-specific data to guide decision-making. However, there is a need for risk stratification tools that allow for conservative management in low-risk cases.

Malignancy risk stratification and subcategorization of K-TIRADS intermediate suspicion thyroid nodules: a retrospective multicenter study

PURPOSE

This study aimed to develop the ultrasonography (US) criteria for risk stratification of the Korean Thyroid Imaging Reporting and Data System (K-TIRADS) 4 nodules, and to evaluate the diagnostic yield of a modified biopsy criterion in a multicenter cohort.

METHODS

In total, 1,542 K-TIRADS 4 nodules (≥1 cm) were included in the study. US criteria for the subcategorization of K-TIRADS 4 nodules were developed based on high-risk US features. The diagnostic yields and false referral rates of biopsy criterion 1 (size cut-off of 1 cm), biopsy criterion 2 (size cut-off of 1.5 cm), and modified biopsy criterion 3 (size cut-off of 1 cm for K-TIRADS 4B and 1.5 cm for K-TIRADS 4A) were evaluated.

RESULTS

The five high-risk US features (solid composition, marked hypoechogenicity, macrocalcification, punctate echogenic foci, and irregular margin) independently increased the malignancy risk of the K-TIRADS 4 nodules (P<0.001). The K-TIRADS 4 nodules could be subcategorized into higher- and lower-risk subcategories according to the number of high-risk US features: K-TIRADS 4B (≥2 US features) and K-TIRADS 4A (≤1 US feature). The modified biopsy criterion increased the diagnostic yield by 7.8% compared with criterion 2 and reduced the false referral rate by 15.3% compared with criterion 1 (P<0.001).

CONCLUSION

The K-TIRADS 4 nodules were subcategorized as K-TIRADS 4B and K-TIRADS 4A based on high-risk US features. The modified biopsy criterion 3 showed a similar diagnostic yield and reduced false referral rate compared to criterion 1.