Objective: FNA is a simple, safe, cost-effective and accurate diagnostic tool for the initial screening of patients with thyroid nodules. The aims of this study were to determine the diagnostic utility of FNAC performed in our institution, assess the cytomorphologic features that contribute to diagnostic errors and propose improvement measures.Methods: A total of 2781 FNACs were included in the study, and 1122 cases were compared with their histological diagnoses. We retrospectively reexamined our discordant (both false-negative and false-positive) cases and performed a systematic review of previous studies on causes of misdiagnoses.Results: When DC V and DC VI were both considered cytologic-positive, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy were 98.3, 30.9, 94.9, 58.3 and 93.5%, respectively. If DC VI was considered cytologic-positive, the sensitivity, specificity, PPV, NPV and diagnostic accuracy of FNAC were 98.0, 84.0, 99.4, 58.3, and 97.5% respectively. The main cause of false-negative diagnoses was sampling error (13/15, 86.7%), while interpretation error led to the majority of the false-positive diagnoses (38/47, 80.9%). Overlapping cytological features in adenomatous hyperplasia, thyroiditis and cystic lesions were the major factors contributing to interpretation errors, while the size and number of nodules may have led to false-negative diagnoses because of heterogeneity and unsampled areas.Conclusions: The sensitivity and PPV of thyroid FNAC in our institution were higher than those in the published data, while the specificity and NPV were lower. Regarding the FNA category DC V, a frozen section analysis during diagnostic lobectomy is necessary. Multiple passes should be performed in various parts of a large nodule or from different nodules to reduce the risk of false-negative findings. Cytopathologists should strengthen their criteria for the identification of adenomatous hyperplasia, thyroiditis and cystic lesions to avoid false-positive diagnoses. NIFTP has little effect on diagnostic accuracy and the distribution of diagnostic errors.

AbstractWith regard to the state-of-the-art technologies in the fields of applied superconductivity and electromagnetic devices, research and development highlights are presented. The recent progress and achievement described with principle and technical details include mainly i) applied superconducting materials; ii) superconducting magnets and their applications such as in ITER and Tokamaks; iii) high Tc superconducting (HTS) magnetic levitation and applications; iv) HTS smart grids; v) superconducting and electromagnetic material modelling and characteristics; vi) advanced electromagnetic devices. The applied superconductivity technology and availability are especially focused and verified with the trend of its development prospection.

Background: Thyroid nodules are highly prevalent, with fine‐needle aspiration (FNA) commonly used as the standard preoperative tool for their diagnosis. However, the method classifies some of the samples as indeterminate, leading to unnecessary surgery. In this study, we evaluated the value of next‐generation sequencing (NGS) for cancer diagnosis in indeterminate thyroid nodules.Materials and methods: We performed a prospective, blinded cohort study on 189 patients, with 196 Bethesda III/IV nodules. Specifically, we analyzed DNA mutations and RNA fusions across the FNA samples using NGS, then reviewed follow‐up reports from 84 nodules following definitive surgery, to determine the assay performance.Results: Enough DNA and RNA were obtained in 188 nodules, revealing mutations or fusions in 34.6% of them. The most frequently mutated genes were RAS, followed by BRAF V600E. Based on surgical pathology, 39% (33/84) and 4.8% (4/84) of the nodules were malignant and intermediate, respectively. According to the risk stratification criteria, 28 cases were categorized High‐Risk group, all of the resected nodules (n = 20) were malignant. Twenty‐four thyroid nodules were in the Low‐Risk group, 28.6% (4/14) surgically removed nodules were malignant. In the Benign‐Like category, 18.0% (9/50) were malignant. Five out of 13 nodules with benign mutations were resected, including SPOP, EZH1, and ZNF148, all of them were benign. If genetic alterations annotated with High‐Risk or Low‐Risk was considered as positive, and negative if Benign‐Like. Multigene testing revealed sensitivity, specificity, positive predictive values (PPV), and negative predictive value (NPV) of 73%, 80%, 71%, and 82%, respectively. In addition, if four intermediate nodules were counted as malignant, the PPV and NPV were 71% and 74%.Conclusion: Our results allow for further stratification of Bethesda III/IV thyroid nodules based on the risk of their malignancy. SPOP, EZH1, and ZNF148 mutations may be used as benign markers.

ObjectiveTo evaluate the diagnostic utility of The Bethesda System for Reporting Thyroid Cytology (TBSRTC) at Peking University Cancer Hospital, the incidence of noninvasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTP), and the impact of reclassification on cytopathological outcomes. MethodsWe performed a retrospective study of thyroid fine-needle aspiration (FNA) cases between April 2014 and March 2019. The FNA results were classified according to TBSRTC. Post-surgery histological findings were followed up. ResultsA total of 2,781 thyroid FNAs were performed. The incidences of the 6 diagnostic categories (DCs I−VI) were 14.8%, 17.1%, 15.8%, 2.3%, 11.6% and 38.5%, respectively. A total of 1,122 patients (40.3%) had corresponding histological results. NIFTP accounted for 0.4% of papillary thyroid carcinoma (PTC) cases, and there was no significant difference in the risk of malignancy (ROM) for each TBSRTC DC between “NIFTP=carcinoma (Ca)” and “NIFTP≠Ca”. When “NIFTP=Ca”, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of TBSRTC were 98.0%, 84.0%, 99.4%, 58.3%, and 97.5%, respectively. When “NIFTP≠Ca”, the sensitivity, specificity, PPV, NPV and accuracy of the TBSRTC were 98.1%, 81.5%, 99.3%, 61.1%, and 97.5%, respectively. ConclusionsTBSRTC is effective in the preoperative diagnosis of thyroid nodules in Peking University Cancer Hospital. The impact of the reclassification of NIFTP on cytopathological outcomes is limited because of its low incidence, and the revised ROMs are not suitable for Asian patients.