Korean Thyroid Association Guidelines on the Management of Differentiated Thyroid Cancers; Part I. Initial Management of Differentiated Thyroid Cancers - Chapter 3. Perioperative Assessment of Surgical Complications 2024

Thyroid surgery complications include voice change, vocal fold paralysis, and hypoparathyroidism. The voice status should be evaluated pre- and post-surgery. In patients with voice change, laryngeal visualization is needed.Intraoperative neuromonitoring helps reduce recurrent laryngeal nerve injury. The measurement of serum calcium, parathyroid hormone, and 25-hydroxyvitamin D levels is recommended to evaluate perioperative parathyroid function and prescribe supplementation preoperatively if necessary. For postoperative hypoparathyroidism, vitamin D and oral calcium supplementation are indicated based on serum parathyroid hormone and calcium levels and the severity of symptoms or signs of hypocalcemia. If long-term treatment is required, the appropriateness of treatment should be evaluated based on the disease itself and the consideration of potential benefits and harms from long-term replacement.

Korean Thyroid Association Guidelines on the Management of Differentiated Thyroid Cancers; Overview and Summary 2024

Differentiated thyroid cancer demonstrates a wide range of clinical presentations, from very indolent cases to those with an aggressive prognosis. Therefore, diagnosing and treating each cancer appropriately based on its risk status is important. The Korean Thyroid Association (KTA) has provided and amended the clinical guidelines for thyroid cancer management since 2007. The main changes in this revised 2024 guideline include 1) individualization of surgical extent according to pathological tests and clinical findings, 2) application of active surveillance in low-risk papillary thyroid microcarcinoma, 3) indications for minimally invasive surgery, 4) adoption of World Health Organization pathological diagnostic criteria and definition of terminology in Korean, 5) update on literature evidence of recurrence risk for initial risk stratification, 6) addition of the role of molecular testing, 7) addition of definition of initial risk stratification and targeting thyroid stimulating hormone (TSH) concentrations according to ongoing risk stratification (ORS), 8) addition of treatment of perioperative hypoparathyroidism, 9) update on systemic chemotherapy, and 10) addition of treatment for pediatric patients with thyroid cancer.

Effectiveness and Usefulness of Bone Turnover Marker in Osteoporosis Patients: A Multicenter Study in Korea

Background@#This study aimed to investigate real-world data of C-terminal telopeptide (CTX), propeptide of type I collagen (P1NP), and osteocalcin through present multicenter clinical study, and retrospectively analyze the usefulness of bone turnover markers (BTMs) in Koreans. @*Methods@#The study focused on pre- and post-menopausal patients diagnosed with osteoporosis and excluded patients without certain test results or with test intervals of over 1 year. The demographic data and 3 BTMs (CTX, P1NP, and osteocalcin) were collected. The patients were classified by demographic characteristics and the BTM concentrations were analyzed by the group. @*Results@#Among women with no history of fractures, the levels of P1NP (N=2,100) were 43.544±36.902, CTX (N=1,855) were 0.373 ±0.927, and osteocalcin (N=219) were 10.81 ±20.631. Among men with no history of fractures, the levels of P1NP (N=221) were 48.498±52.892, CTX (N=201) were 0.370±0.351, and osteocalcin (N=15) were 7.868 ±10.674. Treatment with teriparatide increased the P1NP levels after 3 months in both men and women, with a 50% increase observed in women. Similarly, treatment with denosumab decreased the CTX levels after 3 months in both men and women, with a reduction of 50% observed in women. @*Conclusions@#The results of this study can contribute to the accurate assessment of bone replacement status in Koreans. We also provide the P1NP level in the Korean population for future comparative studies with other populations.

Trabecular Bone Score and Central Quantitative Computed Tomography for the Prediction of Vertebral Fragility Fractures in Postmenopausal Women

Background@#We aimed to investigate whether densitometry results and volumetric bone mineral density (vBMD) can predict vertebral fragility fractures (VFF) in postmenopausal women. @*Methods@#We enrolled 271 postmenopausal women aged >45 years who visited our hospital for health check-ups between September 2016 and September 2017. The lumbar spine (LS) and femoral neck (FN) densitometry results and trabecular bone score (TBS) were calculated using dual energy X-ray absorptiometry. vBMD was assessed using central quantitative computed tomography (cQCT). Baseline and follow-up X-ray images were reviewed to evaluate thoracolumbar vertebral compression fractures (CFs), according to the Genant criteria. @*Results@#At baseline, 76 patients (28.0%) had CF. Additional or progressive fractures were noted in 26 participants (9.6%) with a median follow-up of 19.5 months. The median TBS and cQCT were significantly higher in participants without baseline CF than those with baseline CF (p<0.001). During the follow-up, Kaplan–Meier analysis showed that T-scores of the LS and FN <-2.5, degraded microarchitecture based on the TBS (≤1.200), and vBMD <80 mg/cm3 was significantly associated with future osteoporotic CF. The final multivariate Cox regression analysis showed that baseline CF and low TBS and vBMD were significant risk factors for future VFF. @*Conclusions@#Participants with baseline CF and degraded microarchitecture had higher CF predisposition. Moreover, cQCT can predict future vertebral fractures.

Whole-Exome Sequencing in Papillary Microcarcinoma: Potential Early Biomarkers of Lateral Lymph Node Metastasis

Background@#Early identification of patients with high-risk papillary thyroid microcarcinoma (PTMC) that is likely to progress has become a critical challenge. We aimed to identify somatic mutations associated with lateral neck lymph node (LN) metastasis (N1b) in patients with PTMC. @*Methods@#Whole-exome sequencing (WES) of 14 PTMCs with no LN metastasis (N0) and 13 N1b PTMCs was performed using primary tumors and matched normal thyroid tissues. @*Results@#The mutational burden was comparable in N0 and N1b tumors, as the median number of mutations was 23 (range, 12 to 46) in N0 and 24 (range, 12 to 50) in N1b PTMC (P=0.918). The most frequent mutations were detected in PGS1, SLC4A8, DAAM2, and HELZ in N1b PTMCs alone, and the K158Q mutation in PGS1 (four patients, Fisher’s exact test P=0.041) was significantly enriched in N1b PTMCs. Based on pathway analysis, somatic mutations belonging to the receptor tyrosine kinase-RAS and NOTCH pathways were most frequently affected in N1b PTMCs. We identified four mutations that are predicted to be pathogenic in four genes based on Clinvar and Combined Annotation-Dependent Depletion score: BRAF, USH2A, CFTR, and PHIP. A missense mutation in CFTR and a nonsense mutation in PHIP were detected in N1b PTMCs only, although in one case each. BRAF mutation was detected in both N0 and N1b PTMCs. @*Conclusion@#This first comprehensive WES analysis of the mutational landscape of N0 and N1b PTMCs identified pathogenic genes that affect biological functions associated with the aggressive phenotype of PTMC.

Combined Aerobic and Resistance Exercise Training Reduces Circulating Apolipoprotein J Levels and Improves Insulin Resistance in Postmenopausal Diabetic Women

BACKGROUND@#Circulating apolipoprotein J (ApoJ) is closely associated with insulin resistance; however, the effect of exercise on circulating ApoJ levels and the association of ApoJ with metabolic indices remain unknown. Here, we investigated whether a combined exercise can alter the circulating ApoJ level, and whether these changes are associated with metabolic indices in patients with type 2 diabetes mellitus.@*METHODS@#Postmenopausal women with type 2 diabetes mellitus were randomly assigned into either an exercise (EXE, n=30) or control (CON, n=15) group. Participants in the EXE group were enrolled in a 12-week program consisting of a combination of aerobic and resistance exercises. At baseline, 4, 8, and 12 weeks, body composition and metabolic parameters including homeostatic model assessment of insulin resistance (HOMA-IR) and serum ApoJ levels were assessed.@*RESULTS@#In the EXE group, ApoJ levels decreased 26.3% and 19.4%, relative to baseline, at 8 and 12 weeks, respectively. Between-group differences were significant at 8 and 12 weeks (P<0.05 and P<0.001, respectively). In the EXE group, 12 weeks of exercise resulted in significant decreases in body weight, percent body fat, and HOMA-IR indices. Concurrently, weight-adjusted appendicular skeletal muscle mass (ASM/wt) was increased in the EXE group compared with the CON group. Importantly, changes in the ApoJ level were significantly correlated with changes in ASM/wt.@*CONCLUSION@#Exercise training resulted in a significant decrease in the circulating ApoJ level, with changes in ApoJ associated with an improvement in some insulin resistance indices. These data suggest that circulating ApoJ may be a useful metabolic marker for assessing the effects of exercise on insulin resistance.

Association between Serum Free Thyroxine and Anemia in Euthyroid Adults: A Nationwide Study

BACKGROUND@#Studies on the relationship between thyroid function and anemia in the euthyroid range are scarce. We aimed to evaluate the association between anemia and serum free thyroxine (fT4) and thyrotropin (TSH) in euthyroid adults.@*METHODS@#Data on 5,352 participants aged ≥19 years were obtained from the Korea National Health and Nutrition Examination Survey VI (2013 to 2015). Anemia was defined as hemoglobin (Hb) <13 and <12 g/dL for men and women, respectively.@*RESULTS@#Overall, 6.1% of participants had anemia, and more women (9.9%) had anemia than men (2.8%, P<0.001). In multivariate analysis, serum fT4 levels, but not TSH, were positively associated with serum Hb levels in both sexes (P<0.001, each). Serum Hb levels linearly reduced across decreasing serum fT4 quartile groups in both sexes (P<0.001, each). After adjusting for potential confounding factors, participants with low-normal fT4 had 4.4 (P=0.003) and 2.8 times (P<0.001) higher risk for anemia than those with high-normal fT4 among men and women, respectively. When participants were divided into two groups at 50 years of age, in younger participants, men and women with the first quartile were at higher risk of anemia than men with the second quartile (odds ratio [OR], 3.3; P=0.029) and women with the forth quartile (OR, 3.2; P<0.001), respectively. This association was not observed in older participants.@*CONCLUSION@#These results suggest that a low-normal level of serum fT4 was associated with a lower serum Hb level and a higher risk of anemia in euthyroid adults, especially in younger participants.

Measurement and Interpretation of Dual-Energy X-ray Absorptiometry Bone Density Measurements / 대한내과학회지

Dual-energy X-ray absorptiometry (DXA) is a widely used technology used to diagnosis osteoporosis and monitor changes in bone mineral density (BMD). The present paper reviews the clinical application of DXA in evaluating osteoporosis, including indications for BMD testing, interpretation of DXA results, diagnosis of osteoporosis, and serial BMD follow up. As the clinical utility of DXA depends on the quality of the scan acquisition, the precision assessment of DXA is also discussed.

The Relationship between Thyroid Function and Different Obesity Phenotypes in Korean Euthyroid Adults

BACKGROUND: Thyroid disease and metabolic syndrome are both associated with cardiovascular disease. The aim of this study was to investigate the correlation between thyroid hormones and obesity sub-phenotypes using nationwide data from Korea, a country known to be iodine replete.METHODS: This study was based on data obtained from the sixth Korea National Health and Nutrition Examination Survey, administered from 2013 to 2015. A total of 13,873 participants aged ≥19 years were included, and classified into four groups: metabolically healthy non-obesity (MHNO), metabolically healthy obesity (MHO), metabolically unhealthy non-obesity (MUNO), and metabolically unhealthy obesity (MUO) by body fat on the basis of body mass index and metabolic health.RESULTS: At baseline, serum free thyroxine (fT4) values were significantly higher in the MHNO phenotype (MHNO, 1.27±0.01 ng/dL; MHO, 1.25±0.01 ng/dL; MUNO, 1.24±0.01 ng/dL; MUO, 1.24±0.01 ng/dL, P<0.001) in total study population. However, this significant association no longer remained after adjustment for age, urine iodine concentration, and smoking (P=0.085). After adjustment for confounders, statistically significant association was observed between lower thyroid stimulating hormone (TSH) and MHNO phenotype (P=0.044). In men participants (not women), higher fT4 values were significantly associated with MHNO phenotype (P<0.001). However, no significant association was observed between thyroid function (TSH or fT4) and obesity phenotypes in groups classified by age (cutoff age of 55 years).CONCLUSION: Although there was a difference by age and sex, we found that the decrease of TSH and the increase of fT4 values were associated with MHNO.

Use of Bone Turnover Markers in Clinical Practice for the Management of Osteoporosis in Korea: From the Survey on the Prescription Pattern of Bone Turnover Markers

BACKGROUND: There has been interest in the clinical potential of bone turnover markers (BTMs) as tools both for assessing fracture risk and for monitoring treatment. However, the practical use of BTMs has been limited by their biological variability and difficulties in the interpretation of results. We investigated the current situation of application of BTMs by clinicians in Korea for the management of osteoporosis through a survey asking the patterns of BTMs prescription in clinical practice.METHODS: The survey was conducted online using the “google survey” by the BTM committee authorized by the Korean Society for Bone and Mineral Research.RESULTS: Total 108 clinicians responded the survey. Most of the respondents prescribed BTMs (80.6%) when they prescribed anti-osteoporotic medications (AOMs). The most frequently prescribed bone resorption and formation markers were serum C-terminal telopeptide of type I collagen (90.7%) and osteocalcin (65.1%), respectively. BTMs were mostly prescribed before starting AOMs (90.8%) and used for the purpose of evaluating treatment response (74.4%). Treatment response and compliance to AOMs were evaluated according to the change of absolute value of BTMs (55.1%). The respondents complained difficulties in the interpretation of BTMs (33.3%), the choice of proper BTMs (17.2%), and the proper sample preparation and handling (13.8%).CONCLUSIONS: In Korea, most of clinicians recognized the benefit of BTMs in the management of osteoporosis. However, there are limitations in the broad use of these markers in clinical practice. Therefore, a clear recommendation for BTM in Korea enhances their use in clinical practice.

Position Statement on the Use of Bone Turnover Markers for Osteoporosis Treatment

Current evidences continue to support the clinical application of bone turnover markers (BTMs) in the management of postmenopausal osteoporosis. The limitations of bone mineral density measured by dual energy X-ray absorptiomet especially emphasize the beneficial roles of BTMs, such as serum C-terminal telopeptide of type I collagen and serum procollagen type I N-propeptide, as monitoring tools to assess the responses to treatment. Therefore, the proper application and assessment of BTM in clinical practice is very important. However, their use in Korea is still insufficient. Therefore, the BTM committee has set up by the Korean Society for Bone and Mineral Research have been constituted and provided a position statement which will suggest on the clinical application of BTM for the management of postmenopausal osteoporosis in Korea.

Normal Reference Plots for the Bioelectrical Impedance Vector in Healthy Korean Adults

BACKGROUND: Accurate volume measurement is important in the management of patients with congestive heart failure or renal insufficiency. A bioimpedance analyser can estimate total body water in litres and has been widely used in clinical practice due to its non-invasiveness and ease of results interpretation. To change impedance data to volumetric data, bioimpedance analysers use equations derived from data from healthy subjects, which may not apply to patients with other conditions. Bioelectrical impedance vector analysis (BIVA) was developed to overcome the dependence on those equations by constructing vector plots using raw impedance data. BIVA requires normal reference plots for the proper interpretation of individual vectors. The aim of this study was to construct normal reference vector plots of bioelectrical impedance for Koreans. METHODS: Bioelectrical impedance measurements were collected from apparently healthy subjects screened according to a comprehensive physical examination and medical history performed by trained physicians. Reference vector contours were plotted on the RXc graph using the probability density function of the bivariate normal distribution. We further compared them with those of other ethnic groups. RESULTS: A total of 242 healthy subjects aged 22 to 83 were recruited (137 men and 105 women) between December 2015 and November 2016. The centers of the tolerance ellipses were 306.3 Ω/m and 34.9 Ω/m for men and 425.6 Ω/m and 39.7 Ω/m for women. The ellipses were wider for women than for men. The confidence ellipses for Koreans were located between those for Americans and Spaniards without overlap for both genders. CONCLUSION: This study presented gender-specific normal reference BIVA plots and corresponding tolerance and confidence ellipses on the RXc graph, which is important for the interpretation of BIA-reported volume status in patients with congestive heart failure or renal insufficiency. There were noticeable differences in reference ellipses with regard to gender and ethnic groups.

Erratum: Correction of Figure in the Article: Normal Reference Plots for the Bioelectrical Impedance Vector in Healthy Korean Adults

The present erratum notice corrects one figure of the article.

Effects of Thyrotropin Suppression on Bone Health in Menopausal Women with Total Thyroidectomy

BACKGROUND: This study examined the change in the trabecular bone score (TBS), areal bone mineral density (aBMD), and osteoporosis in postmenopausal women who underwent thyrotropin (TSH)-suppressive therapy for treating papillary thyroid cancer after a total thyroidectomy procedure. METHODS: We evaluated 36 postmenopausal women who received a total thyroidectomy for papillary thyroid cancer and were undergoing TSH suppressive therapy with levothyroxine. Postmenopausal women (n=94) matched for age and body mass index were recruited as healthy controls. The aBMD and TBS of the lumbar spine were compared between dual energy X-ray absorptiometry (DXA) at baseline and at follow-up after an average of 4.92 years. RESULTS: There was no significant difference in the rate of diagnoses of osteoporosis, osteopenia, or normal bone status between the 2 groups during the baseline DXA evaluation. However, the TBS was significantly lower whereas aBMD did not show significant difference at the time of baseline DXA measurement (1st DXA, 1.343±0.098 vs. 1.372±0.06317, P < 0.001; 2nd DXA, 1.342±0.095 vs. 1.370±0.062, P < 0.001). The TBS and aBMD did not differ significantly between the initial and follow-up DXA images in both groups of TSH suppressive patients and controls. CONCLUSIONS: The average value of TBS and aBMD did not significantly change during the follow-up period. The TSH suppressive therapy was revealed as not a significant factor for the progressive deterioration of bone status during long term follow-up.

Clinical Application of Bone Turnover Markers in Osteoporosis in Korea

Bone turnover markers (BTMs) have important role in the management of osteoporosis. Recently the clinical application of BTMs has achieved significant progress and measurement of BTMs give us better understanding of pathogenesis of osteoporosis. However, the use of BTMs is still insufficient in Korea. We summarized the available methods and standard interval of the BTMs in Korea. Also we reviewed published literatures on pre-analytical variability in the measurement of BTMs and provided recommendations for standardized sample handling and patient preparation for reducing those pre-analytical variabilities. The clinical application of BTMs in patients with chronic kidney disease who have a higher fracture risk than the general population is summarized.

Measurement and Interpretation of Dual-Energy X-ray Absorptiometry Bone Density Measurements / 대한내과학회지

Dual-energy X-ray absorptiometry (DXA) is a widely used technology used to diagnosis osteoporosis and monitor changes in bone mineral density (BMD). The present paper reviews the clinical application of DXA in evaluating osteoporosis, including indications for BMD testing, interpretation of DXA results, diagnosis of osteoporosis, and serial BMD follow up. As the clinical utility of DXA depends on the quality of the scan acquisition, the precision assessment of DXA is also discussed.

Prevalence of BRAF(V600E) Mutation in Follicular Variant of Papillary Thyroid Carcinoma and Non-Invasive Follicular Tumor with Papillary-Like Nuclear Features (NIFTP) in a BRAF(V600E) Prevalent Area

BACKGROUND: BRAF V600E mutation status and prevalence of non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) has not yet been reported in Korea. The aim of this study was to investigate the significance of the BRAF V600E mutation in the follicular variant of papillary thyroid carcinoma (FVPTC) and to determine the prevalence of NIFTP in BRAF V600E mutation-prevalent Korean patients. METHODS: This study retrospectively analyzed 1,417 consecutive patients who underwent total thyroidectomy with routine prophylactic central lymph node dissection for papillary thyroid carcinoma (PTC). BRAF V600E mutation analysis was performed routinely using multiplex polymerase chain reaction by applying dual priming oligonucleotide. Clinicopathological characteristics and ultrasonographic findings were compared between BRAF V600E mutation-positive and -negative groups for FVPTC. Pathologists reviewed the pathology slides according to consensus diagnostic criteria for the encapsulated FVPTC and NIFTP. RESULTS: The prevalence of the BRAF V600E mutation in all subtypes of PTC was 61.0% (861/1,411). FVPTC presented a BRAF V600E mutation rate of 27.3%. The FVPTC patients with BRAF V600E mutation were older than those with no BRAF V600E mutation (P = 0.021). The prevalence of NIFTP was 0.18% among all PTC patients (2/1,411) and the proportion of NIFTP among FVPTC was 9.1% (2/22). CONCLUSION: The BRAF V600E mutation is prevalent in Korean patients with FVPTC in a region with high frequency of the BRAF V600E mutation and very low prevalence of NIFTP compared with that reported in western studies.

Testosterone and Sarcopenia

Aging affects metabolism, leading to physiological and functional impairments, and is also related to changes in body composition, including reduced skeletal muscle mass and increased body fat. These changes are correlated with the pathophysiology of sarcopenia, which is defined as age-related loss of skeletal muscle mass and strength. Low testosterone levels are associated with unfavorable body composition changes, and sex hormones decrease with aging. Androgen deficiency, along with lack of exercise and poor nutrition, may be among the modifiable contributors to sarcopenia. Testosterone treatment has been reported to have beneficial effects on muscle mass and function, but the results have been inconsistent. Here, we discuss the correlation between testosterone and muscle mass and function, the impact of testosterone on sarcopenia, and the probable mechanisms underlying these effects.

The Effectiveness of Multidisciplinary Team-Based Education in the Management of Type 2 Diabetes / 임상당뇨병

BACKGROUND: Although clinicians, nurse specialists, pharmacists, and nutritionists expend significant time and resources in optimizing care for patients with diabetes, the effectiveness of integrated diabetes care team approach remains unclear. We assessed the effects of a multidisciplinary team care educational intervention on glycated hemoglobin (HbA1c) levels among diabetes patients. METHODS: We conducted a matched case-control study in Korean patients with type 2 diabetes, comparing the propensity scores pertaining to the effectiveness in reducing HbA1c levels between a group receiving an educational intervention and a control group. We included 40 pairs of patients hospitalized between June 2014 and September 2016. HbA1c values measured at baseline, 3 months, and 6 months were compared between the two groups. RESULTS: The educated group showed an improvement in HbA1c levels compared to the control group at 3 months (6.3 ± 2.3% vs. 9.5 ± 4.0%; P = 0.020) and at 6 months (7.5 ± 1.5% vs. 9.6 ± 3.0%; P = 0.106). There was a significant difference in the change in mean HbA1c from baseline to 3 months between the two groups (−35.7 ± 26.1% vs. −9.1 ± 20.5%; P = 0.013). CONCLUSION: A multidisciplinary team care education intervention was advantageous for improving glucose control in patients with type 2 diabetes, and may help to optimize glycemic control in clinical practice.

Changes in Urinary Angiotensinogen Associated with Deterioration of Kidney Function in Patients with Type 2 Diabetes Mellitus

Urinary angiotensinogen (AGT) is potentially a specific biomarker for the status of the intrarenal renin-angiotensin system (RAS) in patients with diabetes mellitus. We explored whether changes in urinary AGT excretion levels were associated with the deterioration of kidney function in type 2 diabetes patients with preserved kidney function. Urinary baseline AGT levels were measured in 118 type 2 diabetic patients who were not taking RAS blockers and who had estimated glomerular filtration rates (eGFRs) ≥ 60 mL/min/1.73 m². A total of 91 patients were followed-up for 52 months. Changes in urinary levels of AGT (ΔAGT) were calculated by subtracting urinary AGT/creatinine (Cr) at baseline from urinary AGT/Cr after 1 year. ΔAGT was significantly inversely correlated with annual eGFR change (β = −0.29, P = 0.006; β = −0.37, P = 0.001 after adjusting for clinical factors). RAS blockers were prescribed in 36.3% of patients (n = 33) during follow-up. The ΔAGT values were lower in the RAS blockers users than in the non-RAS blockers users, but the differences were not statistically significant (7.37 ± 75.88 vs. 22.55 ± 57.45 μg/g Cr, P = 0.081). The ΔAGT values remained significantly correlated with the annual rate of eGFR change (β = −0.41, P = 0.001) in the patients who did not use RAS blockers, but no such correlation was evident in the patients who did. ΔAGT is inversely correlated with annual changes in eGFR in type 2 diabetes patients with preserved kidney function, particularly in RAS blocker-naïve patients.