The increasing detection of papillary thyroid microcarcinoma (PTMC) has raised concerns about overtreatment.For low-risk PTMC, either immediate surgery or active surveillance (AS) can be considered. To support AS implementation, the Korean Thyroid Association convened a multidisciplinary panel and developed the first Korean guideline. AS is recommended to adults with pathologically proven Bethesda V-VI PTMC without clinical evidence of lymph node or distant metastasis, gross extrathyroidal extension, tracheal or recurrent laryngeal nerve invasion, or aggressive histology. Baseline assessment requires high‑resolution cervical ultrasound by experienced operators to rule out extrathyroidal extension, tracheal or recurrent laryngeal nerve invasion, and lymph node metastasis;contrast‑enhanced neck computed tomography is optional. Patient characteristics such as age, comorbidities, and capacity for long-term follow-up should be assessed. Shared decision-making should weigh the benefits and risks of surgery and AS, expected oncologic outcomes, complications, quality of life, anxiety, medical cost, and patient preference. Follow-up includes cervical ultrasound and thyroid function test every six months for two years, then annually. Disease progression, defined as significant tumor growth or newly detected nodal or distant metastasis, warrants surgery. Despite remaining uncertainties, this guideline offers a framework to ensure oncologic safety and support patient-centered active surveillance.

The American Joint Committee on Cancer/Union for International Cancer Control (AJCC/UICC) staging classification of thyroid cancer can predict death but cannot determine the type and frequency of follow-up testing. Risk stratification is a concept proposed by the American Thyroid Association that uses additional prognostic factors that are not included in the AJCC/UICC classification, such as number or size of metastatic lymph nodes, genetic mutations, and vascular invasion in follicular cancer, to further refine the prognosis of thyroid cancer. The risk of recurrence was categorized as low, intermediate, and high risk, and the need for total thyroidectomy, radioiodine therapy, or thyroid-stimulating hormone suppression was determined depending on each risk level. This approach has been accepted worldwide, and the previous recommendations of the Korean Thyroid Association followed a similar line of thinking but these have been modified in the revised 2024 guidelines.For the revised initial risk stratification, after careful review of the results of the recent meta-analyses and large observational studies and after a multidisciplinary meeting, four major changes were made: 1) thyroid cancer was reclassified according to the World Health Organization (WHO) 2022 tumor classification system; 2) recurrence risk was stratified by combining encapsulated follicular variant papillary thyroid cancer, follicular thyroid cancer, and oncocytic thyroid cancer, which have similar recurrence risk and associated factors, into follicular-patterned tumor; 3) low-risk groups were defined as those with a known recurrence rate of ≤5%, high-risk groups were upgraded to those with a known recurrence rate of ≥30%, and intermediate-risk groups were those with a recurrence risk of 5–30%; and 4) the intermediate risk group had the recurrence rate presented according to various clinicopathological factors, mainly based on reports from Korea. Thus, it is recommended to evaluate the initial risk group by predicting the recurrence rate by combining each clinical factor in individual patients, rather than applying the recurrence rate caused by single risk factor.

Surgical resection is typically the primary treatment for differentiated thyroid cancer (DTC), followed by radioactive iodine (RAI) and thyroid-stimulating hormone suppression therapies based on the cancer stage and risk of recurrence. Nevertheless, further treatment may be necessary for patients exhibiting persistent disease following RAI therapy, residual disease refractory to RAI, or unresectable locoregional lesions. This guideline discusses the role of external beam radiotherapy and chemotherapy following surgical resection in patients with DTC. External beam radiotherapy is ineffective if DTC has been entirely excised (Grade 2). Adjuvant external beam radiotherapy may be optionally performed in patients with incomplete surgical resection or frequently recurrent disease (Grade 2). In patients at high risk of recurrence following surgery and RAI therapy, adjuvant external beam radiotherapy may be optionally considered (Grade 3). However, external beam radiotherapy may increase the risk of serious adverse events after tyrosine kinase inhibitor therapy. Therefore, careful consideration is needed when prescribing external beam radiotherapy for patients planning to undergo tyrosine kinase inhibitor therapy. There is no evidence supporting the benefits of the routine use of adjuvant chemotherapy for DTC treatment (Grade 2).

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.

Globally, population aging is a widespread phenomenon. However, Korea is experiencing this demographic shift at the fastest rate globally. As the number of older adults increases, the local primary healthcare system has become increasingly important in supporting them to maintain their lives within the community.Current Concepts: The integrated medical support project is systematic and comprehensive, focusing on services provided by primary care providers. The project requires a tailored implementation plan specific to the community for long-term operations. Therefore, providers need to explore roles and collaborative measures to establish a sustainable system of primary care-centered supportive care for elderly patients.Discussion and Conclusion: Local governments must identify patients, establish a cooperative system, manage and entrust patient information and communications technology (ICT), educate ICT users, and secure a budget to integrate and provide medical care in the community effectively. The local medical association should establish and operate a medical and healthcare support center, coordinate a consultative body between medical institutions, and implement a 24-hour patient response system. The proposed medical and healthcare support center will facilitate cooperation and comprehensive evaluation during home visits by primary care doctors. This center can also connect patients needing care by collaborating with local care-related organizations. In addition to providing home-visit services, primary care institutions must establish a system for conducting comprehensive patient evaluations with medical care support teams. Additionally, the recommendation is to incorporate elements beyond home-visit treatment fees to facilitate the systematic and intensive management of patients.

Each country is providing various community care services owing to the increasingly aging population. Therefore, Korea needs to develop multiple approaches to the healthcare utilization system that can reflect the complex needs of older adult patients.Current Concepts: Considering the characteristics of older adult patients, it is essential to connect the treatment at medical institutions with home or nursing facilities. Some patients need medical and long-term healthcare simultaneously. Currently, healthcare services for older adult patients in Korea are fragmented across various service areas. Therefore, healthcare service plans need to be explored to provide integrated and long-term healthcare for older adult patients.Discussion and Conclusion: We propose to establish a healthcare information linkage center to provide comprehensive information on the appropriate services needed by patients. The healthcare information linkage center would refer patients to their local community or local primary healthcare provider if they want home services. Through this process, doctors and healthcare teams would visit the patient’s residence to provide services and perform a comprehensive assessment of their condition to create a personalized care plan. The core of this proposal lies in the establishment of a single point of contact in the region to link and integrate healthcare. Consequently, information on services appropriate to the needs of the target population would be appropriately linked in one place and overlapping services would be coordinated to improve operational efficiency.

Purpose: This study investigated the ultrasound (US) features of malignancy in patients with Hürthle cell neoplasms (HCNs) of the thyroid gland. Methods: The present study included 139 HCNs that had undergone surgical excision at a single institution from 1996 to 2020 and had preoperative US images. The sonographic characteristics of HCNs were correlated with their pathological results. The US findings associated with malignancy were explored using logistic regression analysis, and the diagnostic performance and cutoff were assessed using receiver operating characteristic analysis. Results: The most common US findings of HCNs were a solid content (76.3%), oval to round shape (100%), hypoechogenicity (70.5%), a smooth margin (95.0%), the halo sign (90.6%), and no calcifications (93.5%). HCNs were commonly smaller in pathologic measurements than in US measurements (smaller, same, and greater than US measurements in 60.4%, 21.6%, and 18.0% of HCNs, respectively; P<0.001). On US, malignant nodules were significantly larger than benign nodules (3.4±1.6 cm vs. 2.2±1.2 cm, P<0.001). Multiple logistic regression showed that the US tumor size was an independent predictor of malignancy (P=0.001; odds ratio, 1.730 for a 1-cm increase [95% confidence interval, 1.258 to 2.375]). The best cutoff US tumor size for predicting malignancy was 3.35 cm (sensitivity, 53.1%; specificity, 87.9%). Conclusion The US tumor size was found to be an independent predictor of malignancy in HCNs, and a US tumor size >3.35 cm might be used as a criterion to suggest malignancy. The size of HCNs often showed discrepancies between US and pathologic measurements.

Objective: Glucagon in mammals and its homolog (adipokinetic hormone [AKH] in Drosophila melanogaster) are peptide hormones which regulate lipid metabolism by breaking down triglycerides. Although regulatory mechanisms of glucagon and Akh expression have been widely studied, post-transcriptional gene expression of glucagon has not been investigated thoroughly. In this study, we aimed to profile proteins binding with Gcg messenger RNA (mRNA) in mouse and Akh mRNA in Drosophila. Methods: Drosophila Schneider 2 (S2) and mouse 3T3-L1 cell lysates were utilized for affinity pull down of Akh and Gcg mRNA respectively using biotinylated anti-sense DNA oligoes against target mRNAs. Mass spectrometry and computational network analysis revealed mRNA-interacting proteins residing in functional proximity. Results: We observed that 1) 91 proteins interact with Akh mRNA from S2 cell lysates, 2) 34 proteins interact with Gcg mRNA from 3T3-L1 cell lysates. 3) Akh mRNA interactome revealed clusters of ribosomes and known RNA-binding proteins (RBPs). 4) Gcg mRNA interactome revealed mRNA-binding proteins including Plekha7, zinc finger protein, carboxylase, lipase, histone proteins and a cytochrome, Cyp2c44. 5) Levels of Gcg mRNA and its interacting proteins are elevated in skeletal muscles isolated from old mice compared to ones from young mice. Conclusion Akh mRNA in S2 cells are under active translation in a complex of RBPs and ribosomes. Gcg mRNA in mouse precursor adipocyte is in a condition distinct from Akh mRNA due to biochemical interactions with a subset of RBPs and histones. We anticipate that our study contributes to investigating regulatory mechanisms of Gcg and Akh mRNA decay, translation, and localization.

Background and Objectives: We investigated whether extra-pulmonary vein (PV) ablation targeting a high maximal slope of the action potential duration restitution curve (Smax) improves the rhythm outcome of persistent atrial fibrillation (PeAF) ablation. Methods: In this open-label, multi-center, randomized, and controlled trial, 178 PeAF patients were randomized with 1:1 ratio to computational modeling-guided virtual Smax ablation (V-Smax) or empirical ablation (E-ABL) groups. Smax maps were generated by computational modeling based on atrial substrate maps acquired during clinical procedures in sinus rhythm. Smax maps were generated during the clinical PV isolation (PVI). The V-Smax group underwent an additional extra-PV ablation after PVI targeting the virtual high Smax sites. Results: After a mean follow-up period of 12.3±5.2 months, the clinical recurrence rates (25.6% vs. 23.9% in the V-Smax and the E-ABL group, p=0.880) or recurrence appearing as atrial tachycardia (11.1% vs. 5.7%, p=0.169) did not differ between the 2 groups. The postablation cardioversion rate was higher in the V-Smax group than E-ABL group (14.4% vs. 5.7%, p=0.027). Among antiarrhythmic drug-free patients (n=129), the AF freedom rate was 78.7% in the V-Smax group and 80.9% in the E-ABL group (p=0.776). The total procedure time was longer in the V-Smax group (p=0.008), but no significant difference was found in the major complication rates (p=0.497) between the groups. Conclusions Unlike a dominant frequency ablation, the computational modeling-guided V-Smax ablation did not improve the rhythm outcome of the PeAF ablation and had a longer procedure time.