1.Korean Thyroid Association Guidelines on the Management of Differentiated Thyroid Cancers; Part II. Follow-up Surveillance after Initial Treatment 2026
Eun Kyung LEE ; Seung Heon KANG ; Bon Seok KOO ; Mijin KIM ; Min Joo KIM ; Bo Hyun KIM ; Ji Won KIM ; Dong Gyu NA ; Sohyun PARK ; Ji-In BANG ; Kyorim BACK ; Youngduk SEO ; Young-Ik SON ; Young Shin SONG ; Dong Yeob SHIN ; Jong-Hyuk AHN ; Hwa Young AHN ; So Won OH ; Ho-Ryun WON ; Won Sang YOO ; Min Kyoung LEE ; Sang-Woo LEE ; Jeongmin LEE ; Ji Ye LEE ; Dong-Jun LIM ; Ki-Wook CHUNG ; Ari CHONG ; Jin Hyang JUNG ; Sun Wook CHO ; Yoon Young CHO ; Chae Moon HONG ; Young Joo PARK ;
International Journal of Thyroidology 2026;19(1):1-40
In patients with differentiated thyroid cancer (DTC), initial recurrence risk stratification based on clinical, histopathological, and perioperative data remains the key determinant for guiding management strategies during the first 1-2 years post-treatment. However, the adoption of ongoing risk stratification (ORS), which dynamically reassesses risk by integrating longitudinal clinical data and treatment response, enables more precise long-term prognostic assessment and facilitates highly individualized management. Building upon recent guidelines, the 2026 KTA guideline has been further refined by incorporating robust evidence from large-scale national cohorts and comprehensive systematic reviews. These updated recommendations outline contemporary concepts of ORS, risk-adapted TSH suppression targets, optimized surveillance modalities for recurrence detection, and disease-specific long-term follow-up strategies. Reflecting the paradigm shift toward de-escalated treatment, this revision integrates evolved perspectives on TSH suppression intensity, the clinical interpretation of thyroglobulin levels, and tailored follow-up intervals. These evidence-based recommendations aim to minimize unnecessary treatment and excessive surveillance in the large proportion of patients with excellent prognosis after initial therapy, while ensuring that each patient receives appropriately tailored and effective long-term management.
2.Considerations of Flow Cytometric Lymphocyte Subset Analysis in Korea Based on a Survey of Current Clinical Laboratory Practice
Mikyoung PARK ; Hyun-Woo CHOI ; Jihyang LIM ; Kyung-Hwa SHIN ; Eun-Jee OH ; Jaewoo SONG ; Kyeong-Hee KIM ; In Hwa JEONG ; Joo-Heon PARK ; Sang-Hyun HWANG ; Eun-Suk KANG
Annals of Laboratory Medicine 2026;46(2):220-225
Flow cytometric lymphocyte subset analysis (FCLSA) is essential for assessing immune status across various diseases and clinical settings. We surveyed current clinical laboratory practices related to FCLSA to establish a baseline reference for future standardization in Korea. Nine university hospitals actively performing FCLSA responded to the 22-question survey, which covered seven categories of laboratory practice. These hospitals used commercial reagent antibody kits from either Beckton Dickinson Biosciences (N = 4) or Beckman Coulter Diagnostics (N = 5). Most hospitals performed daily instrument setup and scheduled maintenance every 2–6 months. Two levels of commercial quality control materials were routinely used each day. Sample and reagent antibody volumes varied across hospitals, even when the same reagent kit was used. Acquired cell counts ranged from 5 × 10 3 to 5 × 10 4 cells, with two hospitals adjusting counts based on the cell type analyzed. Most laboratories reported percentages and general opinions; some additionally reported white blood cell and lymphocyte counts, along with lymphocyte percentages. This is the first comprehensive survey on the clinical laboratory practice of FCLSA in Korea.Standardization of FCLSA should be accelerated to ensure reliable and reproducible results.
3.Transition to a Primary Care–Centered Healthcare System: A Structural Reform for Korean Healthcare
Serng Bai PAK ; Sang-Hyun LEE ; Kyung-Hee CHO ; Juhwan OH ; Sang-il LEE ; Kunhee PARK ; Jae-Heon KANG ; Seung-Won OH ; Hee Gyung KANG ; Mihwa YOO
Korean Journal of Family Practice 2026;16(1):33-41
Korea’s healthcare system is at a critical juncture as rapid population aging, rising chronic disease burdens, and fragmented care expose the limits of a hospital-centered, fee-for-service model. Although policy discussions have long emphasized strengthening primary care and introducing a “family doctor” system, past reforms have focused mainly on expanding services or redefining professional roles, without establishing clear accountability, care continuity, or aligned payment mechanisms. Consequently, primary care remains weak and responsibility for comprehensive patient management is diffuse. This article argues that meaningful reform requires redefining the primary physician as an accountable manager of longitudinal, coordinated care within an integrated delivery and payment framework. Drawing on experiences from the United States, the United Kingdom, and several European countries, it identifies common features of successful primary care–oriented systems, including patient registration, team-based care, risk-adjusted payment, and explicit outcome accountability. Based on these insights, the authors propose a Korean primary physician model tailored to solo and small-group practices while fostering regional collaboration. Core elements include voluntary patient registration, multidisciplinary primary care teams, risk-stratified care management, regional care networks, and a mixed payment model combining per-member-per-month payments, shared savings, and performance-based incentives. The article emphasizes phased pilot testing focused on operational feasibility. Ultimately, transitioning to a primary care–centered system is presented as a strategic necessity for sustainability and improved care continuity.
4.Outcomes of Deferring Percutaneous Coronary Intervention Without Physiologic Assessment for Intermediate Coronary Lesions
Jihoon KIM ; Seong-Hoon LIM ; Joo-Yong HAHN ; Jin-Ok JEONG ; Yong Hwan PARK ; Woo Jung CHUN ; Ju Hyeon OH ; Dae Kyoung CHO ; Yu Jeong CHOI ; Eul-Soon IM ; Kyung-Heon WON ; Sung Yun LEE ; Sang-Wook KIM ; Ki Hong CHOI ; Joo Myung LEE ; Taek Kyu PARK ; Jeong Hoon YANG ; Young Bin SONG ; Seung-Hyuk CHOI ; Hyeon-Cheol GWON
Korean Circulation Journal 2025;55(3):185-195
Background and Objectives:
Outcomes of deferring percutaneous coronary intervention (PCI) without invasive physiologic assessment for intermediate coronary lesions is uncertain.We sought to compare long-term outcomes between medical treatment and PCI of intermediate lesions without invasive physiologic assessment.
Methods:
A total of 899 patients with intermediate coronary lesions between 50% and 70% diameter-stenosis were randomized to the conservative group (n=449) or the aggressive group (n=450). For intermediate lesions, PCI was performed in the aggressive group, but was deferred in the conservative group. The primary endpoint was major adverse cardiac events (MACE, a composite of all-cause death, myocardial infarction [MI], or ischemia-driven any revascularization) at 3 years.
Results:
The number of treated lesions per patient was 0.8±0.9 in the conservative group and 1.7±0.9 in the aggressive group (p=0.001). At 3 years, the conservative group had a significantly higher incidence of MACE than the aggressive group (13.8% vs. 9.3%; hazard ratio [HR], 1.49; 95% confidence interval [CI], 1.00–2.21; p=0.049), mainly driven by revascularization of target intermediate lesion (6.5% vs. 1.1%; HR, 5.69; 95% CI, 2.20–14.73;p<0.001). Between 1 and 3 years after the index procedure, compared to the aggressive group, the conservative group had significantly higher incidence of cardiac death or MI (3.2% vs.0.7%; HR, 4.34; 95% CI, 1.24–15.22; p=0.022) and ischemia-driven any revascularization.
Conclusions
For intermediate lesions, medical therapy alone, guided only by angiography, was associated with a higher risk of MACE at 3 years compared with performing PCI, mainly due to increased revascularization.
5.Outcomes of Deferring Percutaneous Coronary Intervention Without Physiologic Assessment for Intermediate Coronary Lesions
Jihoon KIM ; Seong-Hoon LIM ; Joo-Yong HAHN ; Jin-Ok JEONG ; Yong Hwan PARK ; Woo Jung CHUN ; Ju Hyeon OH ; Dae Kyoung CHO ; Yu Jeong CHOI ; Eul-Soon IM ; Kyung-Heon WON ; Sung Yun LEE ; Sang-Wook KIM ; Ki Hong CHOI ; Joo Myung LEE ; Taek Kyu PARK ; Jeong Hoon YANG ; Young Bin SONG ; Seung-Hyuk CHOI ; Hyeon-Cheol GWON
Korean Circulation Journal 2025;55(3):185-195
Background and Objectives:
Outcomes of deferring percutaneous coronary intervention (PCI) without invasive physiologic assessment for intermediate coronary lesions is uncertain.We sought to compare long-term outcomes between medical treatment and PCI of intermediate lesions without invasive physiologic assessment.
Methods:
A total of 899 patients with intermediate coronary lesions between 50% and 70% diameter-stenosis were randomized to the conservative group (n=449) or the aggressive group (n=450). For intermediate lesions, PCI was performed in the aggressive group, but was deferred in the conservative group. The primary endpoint was major adverse cardiac events (MACE, a composite of all-cause death, myocardial infarction [MI], or ischemia-driven any revascularization) at 3 years.
Results:
The number of treated lesions per patient was 0.8±0.9 in the conservative group and 1.7±0.9 in the aggressive group (p=0.001). At 3 years, the conservative group had a significantly higher incidence of MACE than the aggressive group (13.8% vs. 9.3%; hazard ratio [HR], 1.49; 95% confidence interval [CI], 1.00–2.21; p=0.049), mainly driven by revascularization of target intermediate lesion (6.5% vs. 1.1%; HR, 5.69; 95% CI, 2.20–14.73;p<0.001). Between 1 and 3 years after the index procedure, compared to the aggressive group, the conservative group had significantly higher incidence of cardiac death or MI (3.2% vs.0.7%; HR, 4.34; 95% CI, 1.24–15.22; p=0.022) and ischemia-driven any revascularization.
Conclusions
For intermediate lesions, medical therapy alone, guided only by angiography, was associated with a higher risk of MACE at 3 years compared with performing PCI, mainly due to increased revascularization.
6.Outcomes of Deferring Percutaneous Coronary Intervention Without Physiologic Assessment for Intermediate Coronary Lesions
Jihoon KIM ; Seong-Hoon LIM ; Joo-Yong HAHN ; Jin-Ok JEONG ; Yong Hwan PARK ; Woo Jung CHUN ; Ju Hyeon OH ; Dae Kyoung CHO ; Yu Jeong CHOI ; Eul-Soon IM ; Kyung-Heon WON ; Sung Yun LEE ; Sang-Wook KIM ; Ki Hong CHOI ; Joo Myung LEE ; Taek Kyu PARK ; Jeong Hoon YANG ; Young Bin SONG ; Seung-Hyuk CHOI ; Hyeon-Cheol GWON
Korean Circulation Journal 2025;55(3):185-195
Background and Objectives:
Outcomes of deferring percutaneous coronary intervention (PCI) without invasive physiologic assessment for intermediate coronary lesions is uncertain.We sought to compare long-term outcomes between medical treatment and PCI of intermediate lesions without invasive physiologic assessment.
Methods:
A total of 899 patients with intermediate coronary lesions between 50% and 70% diameter-stenosis were randomized to the conservative group (n=449) or the aggressive group (n=450). For intermediate lesions, PCI was performed in the aggressive group, but was deferred in the conservative group. The primary endpoint was major adverse cardiac events (MACE, a composite of all-cause death, myocardial infarction [MI], or ischemia-driven any revascularization) at 3 years.
Results:
The number of treated lesions per patient was 0.8±0.9 in the conservative group and 1.7±0.9 in the aggressive group (p=0.001). At 3 years, the conservative group had a significantly higher incidence of MACE than the aggressive group (13.8% vs. 9.3%; hazard ratio [HR], 1.49; 95% confidence interval [CI], 1.00–2.21; p=0.049), mainly driven by revascularization of target intermediate lesion (6.5% vs. 1.1%; HR, 5.69; 95% CI, 2.20–14.73;p<0.001). Between 1 and 3 years after the index procedure, compared to the aggressive group, the conservative group had significantly higher incidence of cardiac death or MI (3.2% vs.0.7%; HR, 4.34; 95% CI, 1.24–15.22; p=0.022) and ischemia-driven any revascularization.
Conclusions
For intermediate lesions, medical therapy alone, guided only by angiography, was associated with a higher risk of MACE at 3 years compared with performing PCI, mainly due to increased revascularization.
7.Outcomes of Deferring Percutaneous Coronary Intervention Without Physiologic Assessment for Intermediate Coronary Lesions
Jihoon KIM ; Seong-Hoon LIM ; Joo-Yong HAHN ; Jin-Ok JEONG ; Yong Hwan PARK ; Woo Jung CHUN ; Ju Hyeon OH ; Dae Kyoung CHO ; Yu Jeong CHOI ; Eul-Soon IM ; Kyung-Heon WON ; Sung Yun LEE ; Sang-Wook KIM ; Ki Hong CHOI ; Joo Myung LEE ; Taek Kyu PARK ; Jeong Hoon YANG ; Young Bin SONG ; Seung-Hyuk CHOI ; Hyeon-Cheol GWON
Korean Circulation Journal 2025;55(3):185-195
Background and Objectives:
Outcomes of deferring percutaneous coronary intervention (PCI) without invasive physiologic assessment for intermediate coronary lesions is uncertain.We sought to compare long-term outcomes between medical treatment and PCI of intermediate lesions without invasive physiologic assessment.
Methods:
A total of 899 patients with intermediate coronary lesions between 50% and 70% diameter-stenosis were randomized to the conservative group (n=449) or the aggressive group (n=450). For intermediate lesions, PCI was performed in the aggressive group, but was deferred in the conservative group. The primary endpoint was major adverse cardiac events (MACE, a composite of all-cause death, myocardial infarction [MI], or ischemia-driven any revascularization) at 3 years.
Results:
The number of treated lesions per patient was 0.8±0.9 in the conservative group and 1.7±0.9 in the aggressive group (p=0.001). At 3 years, the conservative group had a significantly higher incidence of MACE than the aggressive group (13.8% vs. 9.3%; hazard ratio [HR], 1.49; 95% confidence interval [CI], 1.00–2.21; p=0.049), mainly driven by revascularization of target intermediate lesion (6.5% vs. 1.1%; HR, 5.69; 95% CI, 2.20–14.73;p<0.001). Between 1 and 3 years after the index procedure, compared to the aggressive group, the conservative group had significantly higher incidence of cardiac death or MI (3.2% vs.0.7%; HR, 4.34; 95% CI, 1.24–15.22; p=0.022) and ischemia-driven any revascularization.
Conclusions
For intermediate lesions, medical therapy alone, guided only by angiography, was associated with a higher risk of MACE at 3 years compared with performing PCI, mainly due to increased revascularization.
8.Developing standardized informed consent for hysterectomy and vulva cancer surgery
Soohyun OH ; Geonwoo LEE ; Kwang-Beom LEE ; Min-Sun KYUNG ; Myounghwan KIM ; Mi-Kyung KIM ; Jaeman BAE ; Min Jong SONG ; Heon Jong YOO ; Dae-Hyung LEE ; Sang-Hun LEE ; Ha Kyun CHANG ; Jae-Weon KIM ; Sang-Yoon PARK
Journal of Gynecologic Oncology 2025;36(6):e107-
Informed consent is a fundamental aspect of surgical care, designed to reinforce patient autonomy, promote shared decision-making, and potentially mitigate legal conflicts by ensuring the provision of comprehensive and consistent information in clinical practice. The Korean Society of Gynecologic Oncology (KSGO) previously published detailed informed consent documents for cervical, endometrial, and ovarian cancer surgery. However, standardized consent forms remain relatively lacking for laparoscopic-robotic hysterectomy performed for non-malignant indications, as well as for vulvar cancer surgery. Hence, the KSGO subcommittee collected, reviewed, and discussed consent forms from domestic medical institutions and subsequently developed informed consent for laparoscopic-robotic hysterectomy and vulvar cancer surgery, aiming to build patient trust and understanding.
10.Current Status of Flow Cytometric Immunophenotyping of Hematolymphoid Neoplasms in Korea
Mikyoung PARK ; Jihyang LIM ; Ari AHN ; Eun-Jee OH ; Jaewoo SONG ; Kyeong-Hee KIM ; Jin-Yeong HAN ; Hyun-Woo CHOI ; Joo-Heon PARK ; Kyung-Hwa SHIN ; Hyerim KIM ; Miyoung KIM ; Sang-Hyun HWANG ; Hyun-Young KIM ; Duck CHO ; Eun-Suk KANG
Annals of Laboratory Medicine 2024;44(3):222-234
Background:
Flow cytometric immunophenotyping of hematolymphoid neoplasms (FCIHLN) is essential for diagnosis, classification, and minimal residual disease (MRD) monitoring. FCI-HLN is typically performed using in-house protocols, raising the need for standardization. Therefore, we surveyed the current status of FCI-HLN in Korea to obtain fundamental data for quality improvement and standardization.
Methods:
Eight university hospitals actively conducting FCI-HLN participated in our survey.We analyzed responses to a questionnaire that included inquiries regarding test items, reagent antibodies (RAs), fluorophores, sample amounts (SAs), reagent antibody amounts (RAAs), acquisition cell number (ACN), isotype control (IC) usage, positiveegative criteria, and reporting.
Results:
Most hospitals used acute HLN, chronic HLN, plasma cell neoplasm (PCN), and MRD panels. The numbers of RAs were heterogeneous, with a maximum of 32, 26, 12, 14, and 10 antibodies used for acute HLN, chronic HLN, PCN, ALL-MRD, and multiple myeloma-MRD, respectively. The number of fluorophores ranged from 4 to 10. RAs, SAs, RAAs, and ACN were diverse. Most hospitals used a positive criterion of 20%, whereas one used 10% for acute and chronic HLN panels. Five hospitals used ICs for the negative criterion. Positiveegative assignments, percentages, and general opinions were commonly reported. In MRD reporting, the limit of detection and lower limit of quantification were included.
Conclusions
This is the first comprehensive study on the current status of FCI-HLN in Korea, confirming the high heterogeneity and complexity of FCI-HLN practices. Standardization of FCI-HLN is urgently needed. The findings provide a reference for establishing standard FCI-HLN guidelines.

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