Background and Objectives: Surgical decision-making for papillary thyroid cancer (PTC) relies on accurate preoperative staging, where ultrasonography plays a crucial role in predicting outcomes. We aimed to analyze the predictive effects of preoperative sonographic findings on pathological characteristics. Materials and Methods: Retrospective study was performed using ultrasonographic images and clinico-pathologic data of papillary thyroid cancer patients who underwent total thyroidectomy or lobectomy between March 2016 and May 2020. Finally, 152 patients and 169 tumors were analyzed. Results: Mean age of patients was 54.2±14.2 years and the proportion of female was 75.7%. Tumor size was 13.6±10.3 mm and the proportions of extrathyroidal extension (ETE) and lymph node (LN) involvement were 52.2% and 23.0%, respectively. Preoperative sonographic findings, including ETE, tumor margin, echogenicity, and K-TIRDAS, were significantly associated with pathological ETE.Other pathological characteristics, including LN involvement, lymphovascular invasion, and resection margin positivity, were more observed in patients with more aggressive findings on preoperative sonography; however, we could not find statistical significances. Conclusion This study showed that preoperative sonographic characteristics, such as sonographic ETE, tumor margin, echogenicity, and K-TIRADS, can provide valuable insights into predicting pathological ETE in PTC patients.

Background and Objectives: Surgical decision-making for papillary thyroid cancer (PTC) relies on accurate preoperative staging, where ultrasonography plays a crucial role in predicting outcomes. We aimed to analyze the predictive effects of preoperative sonographic findings on pathological characteristics. Materials and Methods: Retrospective study was performed using ultrasonographic images and clinico-pathologic data of papillary thyroid cancer patients who underwent total thyroidectomy or lobectomy between March 2016 and May 2020. Finally, 152 patients and 169 tumors were analyzed. Results: Mean age of patients was 54.2±14.2 years and the proportion of female was 75.7%. Tumor size was 13.6±10.3 mm and the proportions of extrathyroidal extension (ETE) and lymph node (LN) involvement were 52.2% and 23.0%, respectively. Preoperative sonographic findings, including ETE, tumor margin, echogenicity, and K-TIRDAS, were significantly associated with pathological ETE.Other pathological characteristics, including LN involvement, lymphovascular invasion, and resection margin positivity, were more observed in patients with more aggressive findings on preoperative sonography; however, we could not find statistical significances. Conclusion This study showed that preoperative sonographic characteristics, such as sonographic ETE, tumor margin, echogenicity, and K-TIRADS, can provide valuable insights into predicting pathological ETE in PTC patients.

Background and Objectives: Surgical decision-making for papillary thyroid cancer (PTC) relies on accurate preoperative staging, where ultrasonography plays a crucial role in predicting outcomes. We aimed to analyze the predictive effects of preoperative sonographic findings on pathological characteristics. Materials and Methods: Retrospective study was performed using ultrasonographic images and clinico-pathologic data of papillary thyroid cancer patients who underwent total thyroidectomy or lobectomy between March 2016 and May 2020. Finally, 152 patients and 169 tumors were analyzed. Results: Mean age of patients was 54.2±14.2 years and the proportion of female was 75.7%. Tumor size was 13.6±10.3 mm and the proportions of extrathyroidal extension (ETE) and lymph node (LN) involvement were 52.2% and 23.0%, respectively. Preoperative sonographic findings, including ETE, tumor margin, echogenicity, and K-TIRDAS, were significantly associated with pathological ETE.Other pathological characteristics, including LN involvement, lymphovascular invasion, and resection margin positivity, were more observed in patients with more aggressive findings on preoperative sonography; however, we could not find statistical significances. Conclusion This study showed that preoperative sonographic characteristics, such as sonographic ETE, tumor margin, echogenicity, and K-TIRADS, can provide valuable insights into predicting pathological ETE in PTC patients.

Background: We aimed to evaluate the clinicopathological features and biological behaviors of Korean thyroid cancer patients with rare variants of papillary thyroid carcinoma (PTC) to address the ambiguity regarding the prognostic consequences of these variants. Methods: We retrospectively reviewed the medical records of 5,496 patients who underwent thyroid surgery for PTC, between January and December 2012, in nine tertiary hospitals. Rare PTC variants included tall cell (TCV), columnar cell (CCV), diffuse sclerosing (DSV), cribriform-morular (CMV), solid (SV), hobnail, and Warthin-like variants. Recurrence-free survival (RFS) was defined as the time from the date of thyroidectomy until recurrence. Results: Rare variants accounted for 1.1% (n=63) of the PTC patients; with 0.9% TCV, 0.02% CCV, 0.1% DSV, 0.1% CMV, and 0.1% SV. The mean age of patients and primary tumor size were 42.1±13.1 years and 1.3±0.9 cm, respectively. Extrathyroidal extension and cervical lymph node metastasis were observed in 38 (60.3%) and 37 (58.7%) patients, respectively. Ultrasonographic findings revealed typical malignant features in most cases. During a median follow-up of 7 years, 6.3% of patients experienced a locoregional recurrence. The 5-year RFS rates were 71.4% in patients with DSV or SV, 95.9% for TCV, or CCV, and 100% for other variants. DSV emerged an independent risk factor associated with shorter RFS. Conclusion In this multicenter Korean cohort, rare variants accounted for 1.1% of all PTC cases, with TCV being the most frequent subtype. DSV emerged as a significant prognostic factor for RFS.

Objective: The number of elderly patients in Korea has been on the rise recently, and hence the number of out-of-hospital cardiac arrest (OHCA) elderly patients is also rising. The causes of cardiac arrest for the elderly vary, and, it is difficult to predict the recovery of spontaneous circulation (ROSC) in OHCA patients. Therefore, the purpose of this study was to ascertain the predictive value of arterial blood gas analysis (ABGA) results in achieving ROSC in the elderly. Methods: A retrospective analysis of emergency department patients with OHCA was performed at the Kangwon National University Hospital, Korea from 1 January 2016 to 31 December 2019. The initial ABGA results were compared between two patient groups, those who had achieved a return of spontaneous circulation and those who had not. Univariate and multivariable analyses were performed to elucidate the factors associated with ROSC. Results: Overall, 229 OHCA patients were included in the final analysis. The lactate level was independently related to ROSC. A receiver operating characteristics (ROC) curve was plotted to obtain the best cutoff value. The lactate level <9.85 mmol/L showed the largest area under the ROC curve (AUC) to predict ROSC (AUC, 0.666; 95% confidence interval, 0.588-0.743). Multiple regression analysis was performed using the cutoff value, which was a lactate level of 9.85 (odds ratio, 2.907; 95% confidence interval, 1.432-5.902; P=0.003). Conclusion The ABGA results during the cardiopulmonary resuscitation of OHCA patients, showed that the lactate level was an independent factor associated with ROSC. The lactate cutoff value was 9.85 mmol/L.

Purpose: To investigate the efficacy and safety of radiofrequency ablation (RFA) for papillary thyroid microcarcinoma (PTMC) after > 10 years of follow-up. Materials and Methods: This study included five patients who underwent RFA to treat PTMCs (five lesions, mean diameter 0.5 cm, range 0.4–0.7 cm) between November 2006 and December 2009. The inclusion criteria were histopathologically confirmed PTMCs, a single PTMC lesion without extrathyroidal extension, no metastasis, and ineligibility or refusal to undergo surgery. RFA was performed by a single radiologist using a radiofrequency generator and an internally cooled electrode. We retrospectively analyzed the procedure-induced complications, serial changes in ablated tumors, recurrence, and local as well as lymph node metastasis based on data obtained from medical records and radiological images. Results: The mean follow-up period was 130.6 months (range 121–159 months). Three patients underwent a single RFA session, and two patients underwent two RFA sessions. We observed no procedure-induced complications. Three tumors completely disappeared after ablation, and ablation of the other two tumors resulted in the formation of a small scar that showed long-term stability (mean duration 16.8 months, range 12–27 months). At the last follow-up, no patient showed recurrence or lymph node metastasis, and serum thyroglobulin levels were within normal limits in all patients. Conclusion RFA may be effective and safe to treat low-risk PTMC in patients who refuse or are ineligible for surgery.

Objective: The number of elderly patients in Korea has been on the rise recently, and hence the number of out-of-hospital cardiac arrest (OHCA) elderly patients is also rising. The causes of cardiac arrest for the elderly vary, and, it is difficult to predict the recovery of spontaneous circulation (ROSC) in OHCA patients. Therefore, the purpose of this study was to ascertain the predictive value of arterial blood gas analysis (ABGA) results in achieving ROSC in the elderly. Methods: A retrospective analysis of emergency department patients with OHCA was performed at the Kangwon National University Hospital, Korea from 1 January 2016 to 31 December 2019. The initial ABGA results were compared between two patient groups, those who had achieved a return of spontaneous circulation and those who had not. Univariate and multivariable analyses were performed to elucidate the factors associated with ROSC. Results: Overall, 229 OHCA patients were included in the final analysis. The lactate level was independently related to ROSC. A receiver operating characteristics (ROC) curve was plotted to obtain the best cutoff value. The lactate level <9.85 mmol/L showed the largest area under the ROC curve (AUC) to predict ROSC (AUC, 0.666; 95% confidence interval, 0.588-0.743). Multiple regression analysis was performed using the cutoff value, which was a lactate level of 9.85 (odds ratio, 2.907; 95% confidence interval, 1.432-5.902; P=0.003). Conclusion The ABGA results during the cardiopulmonary resuscitation of OHCA patients, showed that the lactate level was an independent factor associated with ROSC. The lactate cutoff value was 9.85 mmol/L.

Purpose: To investigate the efficacy and safety of radiofrequency ablation (RFA) for papillary thyroid microcarcinoma (PTMC) after > 10 years of follow-up. Materials and Methods: This study included five patients who underwent RFA to treat PTMCs (five lesions, mean diameter 0.5 cm, range 0.4–0.7 cm) between November 2006 and December 2009. The inclusion criteria were histopathologically confirmed PTMCs, a single PTMC lesion without extrathyroidal extension, no metastasis, and ineligibility or refusal to undergo surgery. RFA was performed by a single radiologist using a radiofrequency generator and an internally cooled electrode. We retrospectively analyzed the procedure-induced complications, serial changes in ablated tumors, recurrence, and local as well as lymph node metastasis based on data obtained from medical records and radiological images. Results: The mean follow-up period was 130.6 months (range 121–159 months). Three patients underwent a single RFA session, and two patients underwent two RFA sessions. We observed no procedure-induced complications. Three tumors completely disappeared after ablation, and ablation of the other two tumors resulted in the formation of a small scar that showed long-term stability (mean duration 16.8 months, range 12–27 months). At the last follow-up, no patient showed recurrence or lymph node metastasis, and serum thyroglobulin levels were within normal limits in all patients. Conclusion RFA may be effective and safe to treat low-risk PTMC in patients who refuse or are ineligible for surgery.

Background: We aimed to evaluate the clinicopathological features and biological behaviors of Korean thyroid cancer patients with rare variants of papillary thyroid carcinoma (PTC) to address the ambiguity regarding the prognostic consequences of these variants. Methods: We retrospectively reviewed the medical records of 5,496 patients who underwent thyroid surgery for PTC, between January and December 2012, in nine tertiary hospitals. Rare PTC variants included tall cell (TCV), columnar cell (CCV), diffuse sclerosing (DSV), cribriform-morular (CMV), solid (SV), hobnail, and Warthin-like variants. Recurrence-free survival (RFS) was defined as the time from the date of thyroidectomy until recurrence. Results: Rare variants accounted for 1.1% (n=63) of the PTC patients; with 0.9% TCV, 0.02% CCV, 0.1% DSV, 0.1% CMV, and 0.1% SV. The mean age of patients and primary tumor size were 42.1±13.1 years and 1.3±0.9 cm, respectively. Extrathyroidal extension and cervical lymph node metastasis were observed in 38 (60.3%) and 37 (58.7%) patients, respectively. Ultrasonographic findings revealed typical malignant features in most cases. During a median follow-up of 7 years, 6.3% of patients experienced a locoregional recurrence. The 5-year RFS rates were 71.4% in patients with DSV or SV, 95.9% for TCV, or CCV, and 100% for other variants. DSV emerged an independent risk factor associated with shorter RFS. Conclusion In this multicenter Korean cohort, rare variants accounted for 1.1% of all PTC cases, with TCV being the most frequent subtype. DSV emerged as a significant prognostic factor for RFS.

Objective: Predicting the incidence of emergency patients can be very important for the efficient use of emergency medical resources and the deployment of 119 centers in a pre-hospital setting. The study was conducted to analyze the occurrence of emergency patients using geographic information systems in a pre-hospital setting in Korea. Methods: The basic data used in this study were collected from the 119 centers in Chuncheon-si, Korea, under the firefighting headquarters in Gangwon-do from January 2012 to December 2016. Results: The total number of patients transferred by 119 paramedics was 72,362. Of these, 9,904 (14.7%) were emergency patients; 519 (0.7%) had cardiovascular diseases; 383 (0.5%) had cerebrovascular diseases; 3,043 (4.2%) were trauma patients; 58,413 (80.7%) were non-emergency patients. The occurrence of emergency diseases was slightly lower in the Hyoja-dong area, and it was slightly higher in the area of the outskirts of the city. The incidence of heart disease was low in the Hyoja-dong and Nam-myeon areas, but the incidence of heart disease was highly observed in other areas. The number of trauma patients was 1,265 (41.6%) in the outskirts of the city, a suburban area, showing a relatively higher incidence than other emerging diseases. Conclusion The deployment of ambulances in Chuncheon-si should be carried out considering demographic characteristics and patient occurrence.