Background/Objectives: Although thyroid lobectomy recently is considered as sufficient for low-risk papillary thyroid carcinoma (PTC), completion thyroidectomy is required due to the insufficiency of the preoperative evaluation. The aim of this study was to investigate recurrence rate and disease free survival depending on the gross extrathyroidal extension (gETE) or the number of metastatic lymph node identified in patients with PTC.Materials & Methods: We assessed 3373 patients with PTC who underwent lobectomy at Seoul St. Mary’s Hospital (Seoul, Korea) between January 2009 and December 2014. Clinicopathological characteristics and long-term surgical outcomes were retrospectively analyzed through complete chart reviews. The mean follow-up duration was 97.1 ± 21.4 months. Results: The rate of recurrence was higher in gETE group (1.8% vs. 6.0%, p=0.004), leading to decreased disease free survival in Kaplan-Meier analysis (log-rank p<0.001). N1 group (n=1389) was analyzed into two groups whether the number of positive nodes is more than 5 or less. For the group of the more metastatic nodes, the recurrence rate higher compared to the other group (3.0% vs. 9.3%, p<0.001). DFS was longer in the group that had lesser metastatic nodes (log-rank p<0.001). However, in terms of N1 group over 1cm (n=492), No statistical difference was observed according to the number of positive lymph nodes (4.5% vs. 9.1%, p=0.092) Conclusion When it comes to node positive PTC, Despite the number of positive lymph nodes was over 5, follow-up with no further surgery can be an option.

Background/Objectives: Pediatric & Adolescent thyroid cancer is a steadily increasing malignancy. We aimed to report our experience at a single tertiary institution and to evaluate the risk factors for recurrence in pediatric & adolescent patients with differentiated thyroid carcinoma (DTC).Materials & Methods: The data of 42 pediatric & adolescent patients (aged ≤19 years) with DTC who underwent thyroidectomy at Seoul St. Mary’s Hospital (Seoul, Korea) between December 1997 and February 2019 were retrospectively reviewed. Clinicopathologic features and surgical outcomes were retrospectively analyzed through complete chart reviews. Results: The mean age was 16.6 years. A total of 6 (14.3%) patients experienced recurrence after initial treatment. The recurrence rate was significantly different between total thyroidectomy (TT) and lobectomy groups (23.1% vs. 0%, p=0.038). However, no statistically significant differences were found in the recurrence rate according to lymph node ratio (LNR) of 0.4 (10.7% vs 21.4%; p=0.383). Multivariate analysis confirmed age (hazard ratio [HR], 0.443; p=0.008) and bilaterality (HR, 11.477; p=0.022) as significant risk factors for DFS. Conclusion Pediatric & Adolescent thyroid cancer is a rare malignancy and TT is recommended as the treatment of choice. However, lobectomy may be considered for Pediatric & Adolescent patients with age >16 years, tumor size <1 cm, and no bilateral disease.

Background/Objectives: Pediatric & Adolescent thyroid cancer is a steadily increasing malignancy. We aimed to report our experience at a single tertiary institution and to evaluate the risk factors for recurrence in pediatric & adolescent patients with differentiated thyroid carcinoma (DTC).Materials & Methods: The data of 42 pediatric & adolescent patients (aged ≤19 years) with DTC who underwent thyroidectomy at Seoul St. Mary’s Hospital (Seoul, Korea) between December 1997 and February 2019 were retrospectively reviewed. Clinicopathologic features and surgical outcomes were retrospectively analyzed through complete chart reviews. Results: The mean age was 16.6 years. A total of 6 (14.3%) patients experienced recurrence after initial treatment. The recurrence rate was significantly different between total thyroidectomy (TT) and lobectomy groups (23.1% vs. 0%, p=0.038). However, no statistically significant differences were found in the recurrence rate according to lymph node ratio (LNR) of 0.4 (10.7% vs 21.4%; p=0.383). Multivariate analysis confirmed age (hazard ratio [HR], 0.443; p=0.008) and bilaterality (HR, 11.477; p=0.022) as significant risk factors for DFS. Conclusion Pediatric & Adolescent thyroid cancer is a rare malignancy and TT is recommended as the treatment of choice. However, lobectomy may be considered for Pediatric & Adolescent patients with age >16 years, tumor size <1 cm, and no bilateral disease.

Background: The presence of telomerase reverse transcriptase (TERT) promoter mutations have been associated with a poor prognosis in patients with papillary thyroid carcinomas (PTC). The frequency of TERT promoter mutations varies widely depending on the population and the nature of the study. Methods: Data were prospectively collected in 724 consecutive patients who underwent thyroidectomy for PTC from 2018 to 2019. Molecular testing for BRAF V600E and TERT promoter mutations was performed in all cases. Results: TERT promoter alterations in two hotspots (C228T and C250T) and C216T were found in 16 (2.2%) and 4 (0.6%) of all PTCs, respectively. The hotspot mutations were significantly associated with older age at diagnosis, larger tumor size, extrathyroidal extension, higher pathologic T category, lateral lymph node metastasis, and higher American Thyroid Association recurrence risk. The patients with C216T variant were younger and had a lower American Thyroid Association recurrence risk than those with hotspot mutations. Concurrent BRAF V600E was found in 19 of 20 cases with TERT promoter mutations. Of 518 microcarcinomas measuring ≤1.0 cm in size, hotspot mutations and C216T variants were detected in five (1.0%) and three (0.6%) cases, respectively. Conclusions Our study indicates a low frequency of TERT promoter mutations in Korean patients with PTC and supports previous findings that TERT promoter mutations are more common in older patients with unfavorable clinicopathologic features and BRAF V600E. TERT promoter mutations in patients with microcarcinoma are uncommon and may have a limited role in risk stratification. The C216T variant seems to have no clinicopathologic effect on PTC.

Background: We aim to validate the diagnostic performance of thyroid core needle biopsy (CNB) for diagnosing malignancy in clinical settings to align with the changes made in recently updated thyroid CNB guidelines. Methods: We retrospectively analyzed 1,381 thyroid CNB and 2,223 fine needle aspiration (FNA) samples. The FNA and CNB slides were interpreted according to the Bethesda System for Reporting Thyroid Cytopathology and updated practice guidelines for thyroid CNB, respectively. Results: Compared to FNA, CNB showed lower rates of inconclusive results: categories I (2.8% vs. 11.2%) and III (1.2% vs. 6.2%), and higher rates of categories II (60.9% vs. 50.4%) and IV (17.5% vs. 2.0%). The upper and lower bounds of the risk of malignancy (ROM) for category IV of CNB were 43.2% and 26.6%, respectively. The CNB subcategory IVb with nuclear atypia had a higher ROM than the subcategory without nuclear atypia (40%–62% vs. 23%–36%). In histologically confirmed cases, there was no significant difference in the diagnostic performance between CNB and FNA for malignancy. However, neoplastic diseases were more frequently detected by CNB than by FNA (88.8% vs. 77.6%, P=0.046). In category IV, there was no difference in unnecessary surgery rate between CNB and FNA (4.7% vs. 6.9%, P=0.6361). Conclusion Thyroid CNB decreased the rate of inconclusive results and showed a higher category IV diagnostic rate than FNA. The revised guidelines for thyroid CNB proved to be an excellent reporting system for assessing thyroid nodules.

Purpose: Recurrent laryngeal nerve injury after thyroid surgery may cause vocal cord palsy (VCP), which leads to unexpected additional costs. In recent years, intraoperative neural monitoring (IONM) has been used to lower the incidence rate of VCP. This study aimed to analyze postoperative management costs for patients with papillary thyroid carcinoma (PTC). Methods: We analyzed the medical records of patients who underwent lobectomy for PTC from September 2018 to August 2019 at The Catholic University of Korea, Seoul St. Mary’s Hospital. A total of 411 patients were enrolled and all the patients had voice examinations. We investigated the total costs in the IONM and non-IONM groups during a maximum 1-year follow-up and calculated the additional costs due to VCP by subtraction of the mean values in each group. Results: The incidence rate of VCP was 3.9% (16 of 411). Extrathyroidal extension was related to VCP in Cox regression tests and accounted for 3.2% (13 of 411). VCP rate did not show a significant difference between the IONM and non-IONM groups (4.1% vs. 3.8%, P = 0.883). Total costs for postoperative management were higher in the IONM group than in the non-IONM group (US $328.2 ± $220.1 vs. $278.7 ± $141.4, P < 0.05). However, the additional costs due to VCP were significantly lower in the IONM group than in the non-IONM group ($474.1 ± $150.3 vs. $568.9 ± $367.6, P < 0.005). Conclusion The use of IONM can mitigate the increase in costs by saving additional expenses associated with VCP.

Purpose: Postoperative adhesions following thyroid surgery can lead to multiple complications that significantly impact quality of life. The use of an acellular dermal matrix (ADM) adhesion barrier device has been proposed as a potential solution to reduce the risk of such adhesions. This study aimed to evaluate the safety and anti-adhesive effect of an ADM in patients undergoing thyroid surgery. Methods: In this multicenter randomized controlled trial, patients undergoing thyroid surgery were randomly assigned to receive either ADM (n = 42) or no ADM (n = 39) during surgery. The primary outcome was the Swallowing Impairment Score (SIS-6), measured 6 weeks after surgery and compared between groups. Secondary outcomes included intergroup comparisons of the SIS-6, the Voice Handicap Index (VHI)-10, and the Glasgow-Edinburgh Throat Scale (GETS) at baseline, and 2, 6, and 18 weeks after surgery. Results: At week 6, the mean SIS-6 scores were 4.0 ± 4.1 and 3.3 ± 4.2 in the ADM and control groups, respectively, which was not significantly different. Both groups showed similar postoperative improvements in SIS-6, VHI-10, and GETS scores over time, without significant differences between groups at any time point, indicating that the ADM did not reduce the incidence of postoperative adhesions or alter the course of recovery compared to the control group. Conclusion Although application of the ADM is safe for use in patients undergoing thyroid surgery, it did not produce a clinically significant advantage in preventing postoperative adhesions. Future research should focus on identifying specific patient populations or surgical scenarios where the use of the ADM may be beneficial.

Purpose: Postoperative adhesions following thyroid surgery can lead to multiple complications that significantly impact quality of life. The use of an acellular dermal matrix (ADM) adhesion barrier device has been proposed as a potential solution to reduce the risk of such adhesions. This study aimed to evaluate the safety and anti-adhesive effect of an ADM in patients undergoing thyroid surgery. Methods: In this multicenter randomized controlled trial, patients undergoing thyroid surgery were randomly assigned to receive either ADM (n = 42) or no ADM (n = 39) during surgery. The primary outcome was the Swallowing Impairment Score (SIS-6), measured 6 weeks after surgery and compared between groups. Secondary outcomes included intergroup comparisons of the SIS-6, the Voice Handicap Index (VHI)-10, and the Glasgow-Edinburgh Throat Scale (GETS) at baseline, and 2, 6, and 18 weeks after surgery. Results: At week 6, the mean SIS-6 scores were 4.0 ± 4.1 and 3.3 ± 4.2 in the ADM and control groups, respectively, which was not significantly different. Both groups showed similar postoperative improvements in SIS-6, VHI-10, and GETS scores over time, without significant differences between groups at any time point, indicating that the ADM did not reduce the incidence of postoperative adhesions or alter the course of recovery compared to the control group. Conclusion Although application of the ADM is safe for use in patients undergoing thyroid surgery, it did not produce a clinically significant advantage in preventing postoperative adhesions. Future research should focus on identifying specific patient populations or surgical scenarios where the use of the ADM may be beneficial.

Purpose: Postoperative adhesions following thyroid surgery can lead to multiple complications that significantly impact quality of life. The use of an acellular dermal matrix (ADM) adhesion barrier device has been proposed as a potential solution to reduce the risk of such adhesions. This study aimed to evaluate the safety and anti-adhesive effect of an ADM in patients undergoing thyroid surgery. Methods: In this multicenter randomized controlled trial, patients undergoing thyroid surgery were randomly assigned to receive either ADM (n = 42) or no ADM (n = 39) during surgery. The primary outcome was the Swallowing Impairment Score (SIS-6), measured 6 weeks after surgery and compared between groups. Secondary outcomes included intergroup comparisons of the SIS-6, the Voice Handicap Index (VHI)-10, and the Glasgow-Edinburgh Throat Scale (GETS) at baseline, and 2, 6, and 18 weeks after surgery. Results: At week 6, the mean SIS-6 scores were 4.0 ± 4.1 and 3.3 ± 4.2 in the ADM and control groups, respectively, which was not significantly different. Both groups showed similar postoperative improvements in SIS-6, VHI-10, and GETS scores over time, without significant differences between groups at any time point, indicating that the ADM did not reduce the incidence of postoperative adhesions or alter the course of recovery compared to the control group. Conclusion Although application of the ADM is safe for use in patients undergoing thyroid surgery, it did not produce a clinically significant advantage in preventing postoperative adhesions. Future research should focus on identifying specific patient populations or surgical scenarios where the use of the ADM may be beneficial.

Background: Recently, active surveillance (AS) has been introduced as an alternative to early surgery (ES) for the management of papillary thyroid microcarcinoma (PTMC), because of its indolent features and low mortality. However, its cost effects have not been determined and the findings of current studies differ, according to each country’s medical system. Methods: A Markov model was constructed to compare the cost-effectiveness of AS and ES, based on a reference case of a 40-year-old patient diagnosed with PTMC. Costs and transition probabilities were derived from previous clinical studies in Korean populations, and the incremental cost-effectiveness ratio (ICER) and net monetary benefit (NMB) were calculated. The willingness-to-pay (WTP) threshold was set at USD 100,000 per quality-adjusted life year (QALY) gained. Sensitivity analyses were conducted to address the uncertainties in the model’s variables. Results: From the base scenario, the cumulative costs and effectiveness were both higher in ES than AS. The ICER for ES, compared with AS, was USD 6,619.86/QALY, lower than the set WTP. The NMB difference between AS and ES increased across the stages (USD 5,980 at the first stage and USD 159,667 at the last stage). The ICER increased along with decreasing age and increasing cost of surgery. The higher the ES utility score and the lower that of AS, the more cost-effective ES, with WTP set at USD 30,000. Conclusion In the current Korean medical system, ES is more cost-effective than AS. ES is more cost-effective as it is diagnosed at young age and followed-up for a long time.