Management Of Papillary Thyroid Carcinoma Research Articles

Cervical lymph node metastasis prediction from papillary thyroid carcinoma US videos: a prospective multicenter study

BackgroundPrediction of lymph node metastasis (LNM) is critical for individualized management of papillary thyroid carcinoma (PTC) patients to avoid unnecessary overtreatment as well as undesired under-treatment. Artificial intelligence (AI) trained by thyroid ultrasound (US) may improve prediction performance.MethodsFrom September 2017 to December 2018, patients with suspicious PTC from the first medical center of the Chinese PLA general hospital were retrospectively enrolled to pre-train the multi-scale, multi-frame, and dual-direction deep learning (MMD-DL) model. From January 2019 to July 2021, PTC patients from four different centers were prospectively enrolled to fine-tune and independently validate MMD-DL. Its diagnostic performance and auxiliary effect on radiologists were analyzed in terms of receiver operating characteristic (ROC) curves, areas under the ROC curve (AUC), accuracy, sensitivity, and specificity.ResultsIn total, 488 PTC patients were enrolled in the pre-training cohort, and 218 PTC patients were included for model fine-tuning (n = 109), internal test (n = 39), and external validation (n = 70). Diagnostic performances of MMD-DL achieved AUCs of 0.85 (95% CI: 0.73, 0.97) and 0.81 (95% CI: 0.73, 0.89) in the test and validation cohorts, respectively, and US radiologists significantly improved their average diagnostic accuracy (57% vs. 60%, P = 0.001) and sensitivity (62% vs. 65%, P < 0.001) by using the AI model for assistance.ConclusionsThe AI model using US videos can provide accurate and reproducible prediction of cervical lymph node metastasis in papillary thyroid carcinoma patients preoperatively, and it can be used as an effective assisting tool to improve diagnostic performance of US radiologists.Trial registrationWe registered on the Chinese Clinical Trial Registry website with the number ChiCTR1900025592.

Optimal thyrotropin level for low-risk papillary thyroid carcinoma after ultrasound-guided radiofrequency ablation

Purpose Maintaining an optimal thyroid stimulating hormone (TSH) level is important in the postoperative management of papillary thyroid carcinoma (PTC). However, there is little evidence for TSH target levels in patients undergoing radiofrequency ablation (RFA). This study aimed to determine the optimal TSH level for management in low-risk patients who underwent RFA. Methods This retrospective propensity score-matched cohort study included patients with low-risk PTC who underwent RFA from January 2014 to December 2018. The patients were categorized into two groups based on the range of TSH levels: low (≤2 mU/L) and high (>2 mU/L) TSH levels. Local tumor progression and disease-free survival (DFS) were compared between the low TSH and high TSH groups, using propensity score analyses based on patient- and tumor-level characteristics. Univariate analyses were performed to select risk factors for tumor progression. Results Overall, our study included 516 patients with low-risk PTC who underwent RFA with a long-term follow-up of 5-years. During follow-up, the overall incidence rate of local tumor progression was 4.8% (25/516), with no significant difference between the matched groups (7/106 [6.6%] vs. 5/53 [9.4%], p = 0.524). DFS did not differ between the two groups (p = 0.5). Moreover, TSH level was not regarded as a significant predictor of tumor progression after Cox analysis; primary tumor size was the only relevant risk factor. Conclusion This large propensity-matched study revealed no association between TSH levels and tumor progression. Thus, for patients with low-risk PTC who underwent RFA, the optimalTSH level is recommended at the euthyroid range.

American Thyroid Association Guidelines and National Trends in Management of Papillary Thyroid Carcinoma

Over time, the American Thyroid Association (ATA) guidelines have increasingly promoted more limited treatments for well-differentiated thyroid cancers. To determine whether the 2009 and 2015 ATA guidelines were associated with changes in the management of low-risk papillary thyroid carcinomas on a national scale. This historical cohort study used the National Cancer Database. All papillary thyroid carcinomas diagnosed from 2004 to 2019 in the National Cancer Database were selected. Patients with tumors of greater than 4 cm, metastases, or clinical evidence of nodal disease were excluded. Data were analyzed from August 1, 2021, to September 1, 2022. The primary aim was to tabulate changes in the rates of thyroid lobectomy (TL), total thyroidectomy (TT), and TT plus radioactive iodine (RAI) therapy after the 2009 and 2015 ATA guidelines. The secondary aim was to determine in which settings (eg, academic vs community) the practice patterns changed the most. A total of 194 254 patients (155 796 [80.2%] female patients; median [range] age at diagnosis, 51 [18-90] years) who underwent treatment during the study period were identified. Among patients who underwent surgery, rates of TL decreased from 15.1% to 13.7% after the 2009 guidelines but subsequently increased to 22.9% after the 2015 changes. Among patients undergoing TT, rates of adjuvant RAI decreased from 48.7% to 37.1% after 2009 and to 19.3% after the 2015 guidelines. Trends were similar for subgroups based on sex and race and ethnicity. However, academic institutions saw larger increases in TL rates (14.9% to 25.7%) than community hospitals (16.3% to 19.5%). Additionally, greater increases in TL rates were observed for tumors 1 to 2 cm (6.8% to 18.9%) and 2 to 4 cm (6.6% to 16.0%) than tumors less than 1 cm (22.8% to 29.2%). In this cohort study among patients with papillary thyroid carcinomas up to 4 cm, ATA guideline changes corresponded with increased TL and reduced adjuvant RAI. These changes were primarily seen in academic institutions, suggesting an opportunity to expand guideline-based care in the community setting.

Endoscopic lateral neck dissection via the breast and transoral approaches for papillary thyroid carcinoma: A preliminary report

Complete lymph node dissection is essential for the management of papillary thyroid carcinoma (PTC) with lymph node metastasis (LNM). This work aimed to describe the feasibility of endoscopic lateral neck dissection via the breast and transoral approach (ELNDBTOA) in PTC patients and the necessity of the addition of the transoral approach. We included 13 patients with PTC and suspected lateral LNM who underwent ELNDBTOA at the Zhongshan Hospital, Xiamen University. Total thyroidectomy, ipsilateral central lymph node dissection, and selective neck dissection (levels IIA, IIB, III, and IV) were performed endoscopically via the breast approach. Residual lymph nodes were further dissected via the transoral approach. The mean operation time was 362.1 ± 73.5 min. In the lateral neck compartments, the mean number of retrieved lymph nodes was 36.6 ± 23.8, and the mean number of positive lymph nodes was 6.8 ± 4.7. In further dissection via the transoral approach, lymph nodes in the lateral neck compartment were obtained in nine patients (9/13, 69.2%), and three patients (3/13, 23.1%) had confirmed lateral neck metastases. Transient hypocalcemia occurred in two patients (2/13, 15.4%), and three patients (3/13, 23.1%) developed transient skin numbness in the mandibular area. No other major complications were observed. There was no evidence of local recurrence or distant metastasis during the follow-up period (range, 24-87 months). All patients were satisfied with the good cosmetic outcome. ELNDBTOA is an option with proven feasibility for select PTC patients with LNM, and the addition of the transoral approach is necessary to ensure complete dissection.

Safety and feasibility of the transoral endoscopic thyroidectomy vestibular approach with neuroprotection techniques for papillary thyroid carcinoma

BackgroundThis study aimed to evaluate the feasibility and safety of the trans-oral endoscopic thyroidectomy vestibular approach (TOETVA) with neuroprotection techniques for the surgical management of papillary thyroid carcinoma (PTC).MethodsPatients with PTC who underwent TOETVA between December 2016 and July 2020 were included in this study, and their relevant clinical characteristics, operational details, and surgical outcomes were reviewed and extracted from their medical records for further analysis.ResultsA total of 75 patients successfully underwent TOETVA with zero conversions. Unilateral lobectomy with isthmectomy and total thyroidectomy were completed for 58 and 17 patients, respectively, all using our unique neuroprotective procedure and ipsilateral central neck dissection (CND). The mean number of retrieved lymph nodes versus positive lymph nodes was 6.8 ± 3.7 vs. 1.5 ± 2.3. Postoperative complications included three cases of transient superior laryngeal nerve (SLN) palsy (4.0%), five cases of transient recurrent laryngeal nerve (RLN) palsy (6.7%), 14 cases of transient hypoparathyroidism (18.7%), two cases of numb chin (2.7%) and two cases of flap perforation (2.7%). The follow-up period for patients with PTC lasted for 15.6 ± 10.9 months, during which no other complications or tumor recurrence were observed.ConclusionTOETVA can be safely performed for patients with PTC with satisfactory results during the short-term follow-up period. Our neuroprotection techniques can be integrated into TOETVA, which is worth recommending for PTC patients who desire better cosmetic surgical outcomes.

Late hypocalcaemia complicating the management of papillary thyroid carcinoma

Late hypocalcaemia complicating the management of papillary thyroid carcinoma

Trends in the Management of Localized Papillary Thyroid Carcinoma in the United States (2000-2018).

Background: In response to evidence of overdiagnosis and overtreatment of papillary thyroid carcinoma (PTC), the 2009 and 2015 American Thyroid Association (ATA) adult guidelines recommended less extensive surgery (lobectomy vs. total thyroidectomy) and more restricted use of postsurgical radioactive iodine (RAI) in management of PTC at low risk of recurrence. In 2015, active surveillance was suggested as a viable option for some <1-cm PTCs, or microcarcinomas. The 2015 ATA pediatric guidelines similarly shifted toward more restricted use of RAI for low-risk PTCs. The impact of these recommendations on low-risk adult and pediatric PTC management remains unclear, particularly after 2015. Methods: Using data from 18 Surveillance, Epidemiology, and End Results (SEER) U.S. registries (2000-2018), we described time trends in reported first-course treatment (total thyroidectomy alone, total thyroidectomy+RAI, lobectomy, no surgery, and other/unknown) for 105,483 patients diagnosed with first primary localized PTC (without nodal/distant metastases), overall and by demographic and tumor characteristics. Results: The declining use of RAI represented the most pronounced change in management of PTCs <4 cm (44-18% during the period 2006-2018), including microcarcinomas (26-6% during the period 2007-2018). In parallel, an increasing proportion of PTCs were managed with total thyroidectomy alone (35-54% during the period 2000-2018), while more subtle changes were observed for lobectomy (declining from 23% to 17% during the period 2000-2006, stabilizing, and then rising from 17% to 24% during the period 2015-2018). Use of nonsurgical management did not meaningfully change over time, impacting <1% of microcarcinomas annually during the period 2000-2018. Similar treatment trends were observed by sex, age, race/ethnicity, metropolitan vs. nonmetropolitan residence, and insurance status. For pediatric patients (<20 years), use of RAI peaked in 2009 (59%), then decreased markedly to 11% (2018), while use of total thyroidectomy alone and, to a lesser extent, lobectomy increased. No changing treatment trends were observed for ≥4-cm PTCs. Conclusions: The declining use of RAI in management of low-risk adult and pediatric PTC is consistent with changing recommendations from the ATA practice guidelines. Post-2015 trends in use of lobectomy and nonsurgical management of low-risk PTCs, particularly microcarcinomas, were more subtle than expected; however, these trends may change as evidence regarding their safety continues to emerge.

Human Endogenous Retrovirus-H Long Terminal Repeat-Associating Protein 2 Possesses Prognostic Significance and Promotes Progression of Papillary Thyroid Cancer.

PurposeIdentification of novel biomarkers could benefit the clinical therapy and management of papillary thyroid carcinoma (PTC). Human endogenous retrovirus long terminal repeat-associating protein 2 (HHLA2) has been reported to play roles in the development of various cancers. The clinical significance and biological function of HHLA2 in PTC were investigated.Patients and MethodsThe expression level of HHLA2 was evaluated in PTC tissues (from 107 PTC patients) and cell lines (TPC-1, IHH-4, CGTH-W3, and MDA-T32 cells) by RT-qPCR. The clinical significance of HHLA2 was estimated with a series of statistical analyses. The biological function of HHLA2 was assessed with the CCK8 assay and transwell assay.ResultsHHLA2 was upregulated in PTC compared with the normal samples and was associated with the positive lymph node metastasis and advanced TNM stage of PTC patients. HHLA2 was an independent prognostic factor associated with the poor survival of PTC patients. Additionally, HHLA2 functioned as a tumor promoter that enhanced the progression of PTC cells.ConclusionHHLA2 could serve as a prognostic biomarker and tumor promoter in PTC, providing a novel therapeutic target of PTC.

Incidental thyroid carcinoma: Correlation between FNAB cytology and pathological examination in 1093 cases

ObjectiveTo investigate Incidental Thyroid Carcinoma (ITC) by comparing the results of Fine Needle Aspiration Biopsy (FNAB) cytology and the postoperative pathological findings. MethodsData of 1479 patients who underwent total thyroidectomy were retrieved. Three hundred eighty-six patients were excluded due to insufficient data. Each surgical specimen studied received two histopathological diagnoses: the local diagnosis ‒ for the same area in which the FNAB was performed; and the final diagnosis, which includes a study of the entire surgical specimen. ResultsA thousand and ninety-three patients were investigated. FNAB result was malignant in 187 patients, benign in 204, suspicious or indeterminate in 668 cases, and inconclusive in 34 cases. The prevalence of ITC was 15.1%. Most of the ITC in this series was less than 0.5 cm. The incidence of ITC was higher in Bethesda III (17.5% ITC) and IV (19% ITC) than in Bethesda II cases (1.5% false negatives and 9% ITC). ConclusionAlthough the incidence of false-negative results in Bethesda II nodules is only 1.5%, 9% of these patients had ITC in the thyroid parenchyma outside the nodule that underwent preoperative FNAB. The incidence of ITC in the same scenario was even higher in Bethesda III (17.5%) and Bethesda IV cases (19%). Ultrasonography-guided FNAB is an excellent method for the assessment of thyroid nodules. However, biopsy sites should be carefully selected. Despite the high incidence of incidentalomas, total thyroidectomy should not always be the treatment of choice due to its rare but potentially serious complications. The findings of the present study can assist future clinical decisions towards active surveillance strategies for the management of papillary thyroid carcinoma.

Hemi-Thyroidectomy versus Total Thyroidectomy in Management of Papillary Thyroid Carcinoma

Hemi-Thyroidectomy versus Total Thyroidectomy in Management of Papillary Thyroid Carcinoma

Surgical management of papillary thyroid carcinoma

Background: Papillary thyroid carcinoma (PTC) is the most prevailing thyroid cancer but remains of a favorable prognosis. Thyroidectomy with excision of all positive cervical nodes remains the cornerstone of the management PTC. The role for prophylactic central neck dissection (PCND) remains controversial. Methods: A prospective non randomised open label study of 20 PTC patients, 8 of them underwent total thyroidectomy with PCND and 12 underwent total thyroidectomy with modified radical neck dissection type III in El Zahraa hospital, Azhar university, and Damanhour oncology center, Egypt starting from September 2019 to August 2021. The incidence of central lymph node metastasis in N0 cases underwent PCND were reported, the relationship between lymph node metastasis with lympho-vascular permeation and capsular invasion, were analysed and sensitivity of fine needle aspiration cytology in diagnosis of PTC was reported.Results: Occult central lymph node metastasis was observed in 62.5% of PTC lesions. The FNAC showed a sensitivity of 85%. Lympho-vascular permeation and capsular invasion showed a sensitivity of 94.12% and 58.82%, respectively for lymph nodes metastasis. Thyroiditis is detected in 50% of cases with PTC. Postoperative ablative dose of radioactive iodine 131 (RAI-131) ranged from 80 to 100 millicurie.Conclusions: R0 resection is mandatory to cure PTC. PCND remains a debatable issue, that needs a large multicentre study with large sample of patients with long term follow up to ascertain the efficacy of PCND in reducing rate of local recurrence, morbidity and mortality.

Management of papillary thyroid carcinoma in children

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Radioactive iodine treatment of papillary thyroid carcinoma in Japan.

We have a unique history of using radioactive iodine (RAI) therapy and surgical treatment for thyroid cancer in Japan. Less than total thyroidectomy without RAI therapy was the most common management of papillary thyroid carcinoma (PTC) in the past. Limited availability of dedicated facilities for the RAI administration due to the strict regulations and insufficient coverage of the expenses were the major reasons that impacted on the management decisions. Following the publication of the Japanese clinical practice guidelines for thyroid tumors in 2010, the risk-adapted approach has become a standard where the high-risk and selected intermediate-risk PTC patients undergo total thyroidectomy followed by RAI therapy and thyrotropin suppression therapy. We are on the shoulders of pioneers who made every effort to bring the interventions closer to an ideal environment for patients. Armed with the revised clinical practice guidelines 2018 and devised inpatient/outpatient RAI therapy, Japanese physicians are ready to proceed to more rational management that would improve patients' outcomes. Directions for the future include further advancement of relevant clinical research to fill the gaps between current evidence and recommendations in the guidelines, and obtaining approval for high-dose RAI therapy on an outpatient basis to improve its effectiveness in both adjuvant and treatment settings.

SUN-473 Primary Hyperparathyroidism and Papillary Thyroid Carcinoma, Association or Coincidence?

Background: The Parathyroid glands originate from the Pharyngeal pouches, Inferior from the third and superior from the fourth. Rarely these glands migrate to the thyroid gland, isthmus or thymus and become ectopic. Primary Hyperparathyroidism (PHPT) is a common cause of hypercalcemia in ambulatory patients. It is also more frequent in women and increases with age. Its treatment is often surgical removal of the affected parathyroid gland. We present a case of an ectopic parathyroid adenoma hidden within the thyroid lobe, treated by thyroid lobectomy ultimately leading to the diagnosis and management of Papillary thyroid carcinoma. Case report: A 73-Year-old female with DM, HTN, hyperlipidemia, osteoporosis was referred to the Endocrine clinic for a history of fractures to the right upper and lower extremities after trivial falls, She was subsequently evaluated for metabolic bone disease, noted to have a PTH 78 (n=14-64 pg/ml) with a total serum calcium 9.7 (n=8.6-10.4 mg/dl), 25-OH Vit-D 14 (n=30-100 ng/ml), urinary calcium to creatinine ratio 20 (n=10-320 mg/g). The parathyroid scan showed persistent activity in the area of the inferior margin right thyroid lobe, suggesting a parathyroid adenoma. She had a parathyroidectomy and during the procedure, the parathyroid gland was unable to be visualized. Hence the Right inferior thyroid lobe was removed. The pathology also showed papillary thyroid carcinoma and the patient had a total thyroidectomy. Discussion: The relationship between PHPT and Papillary thyroid carcinoma still remains unclear. Our patient demonstrated a rare circumstance, wherein the presence of a parathyroid adenoma within the thyroid gland has led to early diagnosis and timely treatment of papillary thyroid carcinoma. Few authors reported thyroid malignancy as the most prevalent cancer among patients with PHPT as the primary disorder. While others report concurrence as a coincidental pathology. Nevertheless, we emphasize the importance of surveillance for thyroid pathology in patients with PHPT that can provide better overall patient outcomes.

Long-term outcomes of patients with papillary thyroid cancer who did not undergo prophylactic central neck dissection.

The role of prophylactic central neck dissection (CND) in the management of papillary thyroid carcinoma (PTC) is controversial. This study reports outcomes of an observational approach in PTC patients without clinical evidence of lymph node metastasis. Patients with PTC who had surgery (without prophylactic CND) between January 2000 and December 2008 were included in this study. Recurrence-free survival (RFS) and disease-specific survival (DSS) were calculated using the Kaplan-Meier method. Cox regression was used in multivariable models. Out of 625 patients, 486 (77.8%) were female, 144 (23%) were aged 55 years or more, 73 (11.7%) had macroscopic extrathyroidal extension, and 79 (12.7%) had pT3 or pT4 disease. Samples were collected from 12 (1.9%) patients with lymph node metastasis in the perithyroidal tissue and 2 (0.3%) patients with lymph node metastasis in the lateral neck lymph tissue for frozen section examination. After a median follow-up of 104 months, the 10-year DSS and RFS rates were 99.7% and 90.2%, respectively. The 10-year lymph node recurrence rate in the central compartment was 2.7%. pT3/4 stage was an independent predictive factor for RFS (P < 0.001, hazard ratio 1.966, 95% confidence interval 1.446-2.673). The outcomes of patients with clinically negative lymph nodes in the central compartment were favorable without prophylactic CND.

Hypocalcemia After Completion Thyroidectomy for Papillary Thyroid Carcinoma.

SUMMARYSurgical management of papillary thyroid carcinoma (PTC) includes total thyroidectomy and lobectomy. After lobectomy, a reoperation called completion thyroidectomy is occasionally required. Postoperative hypocalcemia is the most common complication associated with thyroid surgery. Our main goal was to determine if there is a significant difference between the incidence rate of postoperative hypocalcemia in patients who underwent total thyroidectomy for PTC compared with patients who underwent completion thyroidectomy for PTC. Apart from that, we analyzed the following potential predictive factors for the occurrence of hypocalcemia: sex, age, size of tumor, side of tumor, maximum diameter of individual lobe, occult metastasis, and operating surgeon. The study involved 340 patients who underwent surgery for PTC at the Department of ENT and Head and Neck Surgery, Zagreb University Hospital Centre, between February 25, 2013 and January 3, 2016. Postoperative hypocalcemia incidence rates were higher in the total thyroidectomy group than in the completion thyroidectomy group (37.8% and 29.0%, respectively). However, these differences were not statistically significant. Every analyzed potential predictive factor was proven not to have any correlation with postoperative hypocalcemia. This study demonstrated that there was no significant difference between postoperative hypocalcemia rates in patients who underwent completion thyroidectomy compared with patients who underwent total thyroidectomy for PTC.

Surgical management of papillary thyroid cancer: review of current evidence and consensus

The optimal surgical management of papillary thyroid carcinoma has been an ongoing debate. Most recommendations in clinical practice guidelines are based on large retrospective studies and expert opinion. The objective of the article is to summarize the recent evidence and main arguments related to the surgical management of papillary thyroid carcinoma. A definitive correlation between loco-regional recurrence and long-term survival and the extent of thyroid resection or lymph node dissection have not been established through randomized controlled clinical trials. Due to the low rates of recurrence and mortality associated with papillary thyroid cancer, large scale prospective randomized controlled trials that will help identify the optimal surgical management are unlikely to be available in the future as well. According to current consensus, hemithyroidectomy is sufficient for low-risk disease whereas total thyroidectomy should be performed in those with high-risk features. The place of therapeutic and prophylactic central compartment and lateral neck dissection is discussed based on evidence on short-term and long term outcomes. Furthermore, post-operative staging and dynamic risk stratification are important in determining adjuvant therapy and a follow-up plan.

1866P - Clinical utility of metabolic tumor volume in papillary thyroid carcinoma

BackgroundThe management of papillary thyroid carcinoma (PTC) should be decided by Risk-adapted approach. However, intermediated risk PTC needs to be stratified more precisely. Otherwise, the utility of 18F-FDG PET images in patients with PTC is restrictive. The aim of this study was to investigate the prognostic value of Metabolic Tumor Volume (MTV) measured on 18F-FDG PET images in patients with papillary thyroid carcinoma treated with surgery. MethodsWe retrospectively analyzed 102 patients with PTC who underwent 18F-FDG PET/CT between Feburary 2009 and June 2017 at Osaka University Medical School Hospital for initial staging before surgery. We evaluated the association of MTV of primary tumor (T-MTV) with relapse-free survival (RFS) using Cox regression analysis. Receiver operating characteristic (ROC) curves were used to estimate the optimal cut-off values for T-MTV. We also conducted recursive partitioning analyses to offer a novel risk stratification system. ResultsThe 3-year RFS for all patients were 81.2% with median follow-up of 42 months (range 11-111). In Cox model, T-MTV (Hazard Ratio, 1.23; 95% CI, 1.08 to 1.38; P=0.002) was significantly associated with RFS. ROC analyses showed that the optimal cutoff value of T-MTV was 10.3ml. We classified the patients as having a low, intermediate, or high risk of relapse or death on the basis of T-MTV and lymph node metastasis. ConclusionsMTV of primary tumor was a significant prognostic factor for RFS in patients with PTC treated with surgery. Incorporation of T-MTV into staging may lead to a better risk stratification. Legal entity responsible for the studyThe authors. FundingHas not received any funding. DisclosureAll authors have declared no conflicts of interest.

Sentinel lymph node biopsy in the management of papillary thyroid carcinoma

Sentinel lymph node biopsy in the management of papillary thyroid carcinoma

Discriminatory miRNAs for the Management of Papillary Thyroid Carcinoma and Noninvasive Follicular Thyroid Neoplasms with Papillary-Like Nuclear Features.

Papillary thyroid carcinoma (PTC) variants have several overlapping clinical and pathological features. The World Health Organization recently published a new classification of thyroid tumors containing significant revisions. Encapsulated papillary thyroid carcinoma (EPTC) has been recognized as a distinctive variant of PTC. The noninvasive encapsulated follicular variant of PTC has been reclassified as noninvasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTP). Different neoplasms are associated with different outcomes and require different clinical management. The objective of this study was to explore the miRNA expression patterns specific for classic PTC (cPTC), EPTC, follicular variant of PTC, and NIFTP in order to identify biomarkers of diagnostic and prognostic utility aiming for better clinical decisions. The expression of 84 miRNAs was determined by quantitative real-time polymerase chain reaction in 113 thyroid tissues of PTC (classic, encapsulated, and follicular), NIFTP, and hyperplasia lesions. Expression of the same miRNAs was tested in pre- and postoperative whole-blood samples. Several miRNAs were differentially expressed in the different groups. Expression profile of miRNAs in the tissue was similarly reflected in the circulation. Receiver operating characteristic curve analysis showed that miR-7-5p, miR-222-3p, and miR-146b-5p can discriminate between the different groups with high sensitivity and specificity. Downregulation of miR-144-3p, miR-15a-5p, miR-20a-5p, miR-32-5p miR-142-5p, miR-143-3p, and miR-20b-5p is associated with aggressive behavior in cPTC. Circulating miR-146b-5p, miR-222-3p, miR-155-5p, and miR-378a-3p are potential diagnostic and follow up biomarkers for PTC. Downregulation of miR-7-5p discriminates NIFTP from hyperplasia. Upregulation of miR-222-3p discriminates follicular variant of PTC from NIFTP. High levels of miR-146b-5p distinctively characterize cPTC. These miRNAs are useful biomarkers in the diagnosis of PTC and NIFTP, and help to avoid unnecessary thyroidectomy and improve clinical management.