Best Achievements in Clinical Thyroidology in 2020

Use of long non-coding RNAs for the molecular diagnosis of papillary thyroid cancer

Objective

Improved molecular testing for common somatic mutations and the identification of mRNA and microRNA expression classifiers are promising approaches for the diagnosis of thyroid nodules. However, there is a need to improve the diagnostic accuracy of such tests for identifying thyroid cancer. Recent findings have revealed a crucial role of long non-coding RNAs (lncRNAs) in gene modulation. Thus, we aimed to evaluate the diagnostic value of selected lncRNAs from The Atlas of Noncoding RNAs in Cancer (TANRIC) thyroid cancer dataset.

Methods

LncRNAs in TANRIC thyroid cancer dataset that have significantly increased or decreased expression in papillary thyroid cancer (PTC) tissues were selected as candidates for PTC diagnosis. Surgical specimens from patients who underwent thyroidectomy were used to determine the separation capability of candidate lncRNAs between malignant and benign nodules. Fine needle aspiration samples were obtained and screened for candidate lncRNAs to verify their diagnostic value.

Results

LRRC52-AS1, LINC02471, LINC02082, UNC5B-AS1, LINC02408, MPPED2-AS1, LNCNEF, LOC642484, ATP6V0E2-AS1, and LOC100129129 were selected as the candidate lncRNAs. LRRC52-AS1, LINC02082, UNC5B-AS1, MPPED2-AS1, LNCNEF, and LOC100129129 expression levels were significantly increased or decreased in malignant nodules compared to those in benign nodules and paired normal thyroid tissues. The combination of LRRC52-AS1, LINC02082, and UNC5B-AS1 showed favorable results for the diagnosis of PTC from fine needle aspirates, with 88.9% sensitivity and 100.0% specificity.

Conclusions

LncRNA expression analysis is a promising approach for advancing the molecular diagnosis of PTC. Further studies are needed to identify lncRNAs of additional diagnostic value.

Ultrasound-Guided Fine-Needle Aspiration with or without Negative Pressure for Different Types of Thyroid Nodules

Object

To evaluate the effects of ultrasound-guided fine-needle aspiration with or without negative pressure (FNA+P or FNA-P) on diagnosis of thyroid nodules.

Methods

A prospective randomized study was performed. Patients (n=1374, female=1094, 79.6%, male=280, 20.4%, age=48.7±12.5 yr) with thyroid nodules were randomly divided into FNA-P (n=774, 56.3%) and FNA+P (600, 43.7%) groups. Thyroid nodules were diagnosed by FNA-P or FNA+P, in the left (n=640, 46.6%) and right (n=734, 53.4%).

Results

The thyroid nodules were diagnosed as microcalcification (n=751, 54.7%), coarse calcification (n=404, 29.4%), peripheral calcification (n=101, 7.4%) and mixed micro + coarse calcification (n=118, 8.6%). Based on Bethesda classification criteria, the thyroid nodules were cataloged as type I (n=217,15.8%), II (n=467, 34.0%), III (n=151, 11.0%), V (n=333, 24.2%), and VI (n=206, 15.0%). There were no significant differences between experimental groups diagnosed by FNA-P or FNA+P.

Conclusion

The results suggest that fine-needle aspiration with or without negative pressure does not significantly affect the sensitivity of thyroid nodule diagnosis.