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.Assessment of Fat Fraction and Muscle Atrophy in the Supraspinatus Muscle:Optimal Sagittal Plane Selection in the Shoulder MRI
Chanyoung RHEE ; Hye Jin YOO ; Tae Kun KIM ; Hee Dong CHAE ; Ja-Young CHOI ; Sung Hwan HONG
Investigative Magnetic Resonance Imaging 2026;30(1):29-37
Purpose:
To assess the accuracy of supraspinatus muscle fat fraction and atrophy measured on the Y-view compared with the newly proposed fossa-view sagittal MRI plane.
Materials and Methods:
This study included 84 patients (36 male; mean age, 65.1 ± 10.1 years) who underwent shoulder MRI with extended oblique sagittal T1-weighted and three-dimensional (3D) six-echo Dixon imaging between December 2020 and November 2022. The reference fat fraction was calculated by integrating voxel-wise Dixon values, while supraspinatus muscle volume was quantified using a 3D nnU-Net algorithm and normalized to the scapular volume to derive the standardized muscle index (SMI). Fat fraction and cross-sectional area were quantified on the Y-view and fossaview and compared with the reference values. Subgroup analyses were performed using fatty degeneration and retraction grades.
Results:
Agreement with the reference fat fraction was significantly higher for the fossa-view (intraclass correlation coefficient [ICC], 0.923) than for the Y-view (ICC, 0.822;p = 0.006). The fossa-view showed smaller deviations and narrower limits of agreement.For SMI, the Y-view (ICC, 0.782) showed higher agreement than the fossa-view (ICC, 0.694), although the difference was not statistically significant (p = 0.219). Subgroup analyses showed better Y-view performance at lower retraction grades and better fossa-view performance at higher grades, although the differences were not statistically significant (all p > 0.05).
Conclusion
Both planes reliably quantified the fat fraction with greater accuracy in the fossa-view. However, single-plane assessment of muscle atrophy was less reliable, underscoring the need for MRI evaluation of the entire muscle.
3.The Korean Rectal Cancer Multidisciplinary Committee Clinical Practice Guidelines for Rectal Cancer version 2.0
Hyo Seon RYU ; Hyun Jung KIM ; Dong Hyun KANG ; Yoo-Kang KWAK ; Han Deok KWAK ; Yoon-Hye KWON ; Dalyon KIM ; Baek-Hui KIM ; Jae Hyun KIM ; Ji Hun KIM ; Jin Won KIM ; Tae Hyung KIM ; Hae Young KIM ; Soo Min NAM ; Gyoung Tae NOH ; Jun Woo BONG ; Nak Song SUNG ; Seon Hui SHIN ; Kil-Yong LEE ; Sung Chul LEE ; Sea-Won LEE ; Jung Won LEE ; Jong Min LEE ; Myung Hoon IHN ; Joo Han LIM ; Woong Bae JI ; Dae Hee PYO ; Young Ki HONG ; Jung-Myun KWAK ;
Annals of Coloproctology 2026;42(1):4-33
Rectal cancer, which accounts for approximately 40% of colorectal cancers, remains a major clinical concern. Recent advances in diagnostic imaging, surgical techniques, radiotherapy, and systemic treatment have steadily improved rectal cancer outcomes. Considering this, the Korean Rectal Cancer Multidisciplinary (KRCM) Committee has aimed to provide clinicians and policymakers with up-to-date, evidence-based clinical practice guidelines to support optimal decision-making, reflecting current evidence, the Korean healthcare context, and patient values and preferences. The Clinical Practice Guidelines for Rectal Cancer version 2.0 were developed through multidisciplinary collaboration with related academic societies, building upon and updating the KRCM Clinical Practice Guidelines version 1.0 (titled “Multidisciplinary guidelines for the management of rectal cancer”). These consensus guidelines of the KRCM were established based on a comprehensive literature review, evidence synthesis, with recommendation development guided by the GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology, and consideration of applicability in real-world clinical practice under the national health insurance system. Each recommendation has been presented with its strength and level of evidence.
4.Defect Size-Based Comparative Analysis of Treatment Modalities for Esophagojejunal Anastomotic Leakage Following Gastrectomy
Ba Ool SEONG ; Ji Yong AHN ; Juno YOO ; Chang Seok KO ; Sa-Hong MIN ; Chung Sik GONG ; Beom Su KIM ; Moon-Won YOO ; Jeong Hwan YOOK ; Hee Jin CHOI ; In-Seob LEE
Journal of Gastric Cancer 2026;26(2):295-306
Purpose:
Esophagojejunal anastomotic leakage (EJAL) represents a severe postoperative complication following total or proximal gastrectomy. Treatment strategies include conservative management, endoscopic interventions, and surgery; however, comparative data remain limited. This study aimed to compare clinical outcomes of different strategies to identify the optimal approach based on anastomotic defect size.
Materials and Methods:
This retrospective study reviewed 100 patients diagnosed with EJAL between January 2015 and October 2024. Patients were categorized into four groups:conservative management, endoscopic vacuum-assisted closure (E-VAC), other endoscopic treatments, and surgery. The primary outcomes were leakage duration and length of hospital stay after EJAL diagnosis, whereas the secondary outcome was time to C-reactive protein normalization. Subgroup analyses were performed according to defect size.
Results:
Among the 100 patients, 76 were male and 24 were female, with a mean age of 65.7 years. Conservative treatment was the most common modality (53%), followed by other endoscopic treatments (19%), E-VAC (14%), and surgery (14%). In patients with a defect size <1 cm, conservative treatment was associated with significantly shorter leakage duration (P=0.035) and earlier resumption of diet (P=0.029) compared with endoscopic treatment.Among those with defects ≥2 cm, E-VAC demonstrated the most favorable median outcomes across all variables; however, statistical significance was not achieved because of the small sample size.
Conclusions
Conservative treatment appears to be the most effective treatment strategy for EJAL with anastomotic defects <1 cm. For larger defects (≥2 cm), E-VAC may offer clinical benefit, although further studies are needed to confirm its efficacy. These findings highlight the importance of individualized treatment selection based on defect size.
5.Effectiveness of atorvastatin, methylene blue, and lidocaine as chemical antiadhesion agents in preventing postoperative remote adhesions: a randomized controlled experimental study in a rat model
Young Jin KIM ; Hyun KANG ; Oh Haeng LEE ; Seung Eun LEE ; Soon Auck HONG ; Suk-Won SUH ; Yoo Shin CHOI
Annals of Surgical Treatment and Research 2026;110(1):56-63
Purpose:
We investigated the antiadhesive effects of lidocaine, methylene blue, and atorvastatin, with a focus on preventing remote adhesions in a rat model of postoperative adhesions.
Methods:
Models were assigned to either the control group (saline infusion only) or treatment groups (group L, lidocaine;group M, methylene blue; or group S, atorvastatin). Adhesions were induced by intestinal or abdominal wall injuries. The rats were sacrificed 2 weeks after surgery.
Results:
The number of remote adhesions was markedly lower in groups L, M, and S than in the control group. The macroscopic adhesion score was substantially lower in groups L, M, and S than in the control group. Acute and chronic inflammation, as well as fibrosis scores, were also markedly lower in groups L, M, and S than in the control group. IL-1βlevels were considerably reduced in groups L, M, and S at 2 hours after surgery and remained substantially lower in group S at 48 hours. IL-6 levels were markedly reduced in groups M and S at 2 hours and in all treatment groups at 48 hours than in the control group.
Conclusion
Intraperitoneal administration of lidocaine, methylene blue, and atorvastatin effectively reduced remote adhesion formation, macroscopic and microscopic adhesion scores, and inflammatory cytokine levels in a rat adhesion model.
6.Stress Accelerates Depressive-Like Behaviors through Increase of Notch2 Expression in N141I Mutation Presenilin-2 Transgenic Mice
Seung Sik YOO ; Sun Mi GU ; Kyung Tak NAM ; Jeong Soon CHOI ; Yong Sun LEE ; In Jun YEO ; Ji Eun YU ; Sanghyeon KIM ; Dong Won LEE ; Hyeon Joo HAM ; Ju Young CHANG ; Jaesuk YUN ; Dong Ju SON ; Sang-Bae HAN ; Jin Tae HONG
Biomolecules & Therapeutics 2026;34(3):544-555
Alzheimer’s disease (AD) is characterized by progressive cognitive deterioration and significant depression. However, the mechanisms linking depression to AD pathology remain unclear. Here, we investigated whether Notch2 signaling mediates depressionlike behaviors in presenilin-2 (PS2) N141I mutant mice, an early-onset AD model. PS2 wild-type (WT) and mutant (MT) mice aged 12-15 months were subjected to unpredictable chronic mild stress (UCMS) for 4 weeks, followed by sucrose preference, tail-hanging, and forced swimming tests. Behavioral assessments showed that UCMS exacerbated anhedonia and immobility only in PS2 MT mice. Molecular analysis revealed concomitant increases in plasma corticosterone, hippocampal γ-secretase activity, and Notch2 expression, and elevated total and phosphorylated glucocorticoid receptor levels in PS2 MT-UCMS mice. Gene expression profiling of human hippocampal datasets confirmed upregulation of NOTCH2 in Alzheimer’s disease and depression.Pharmacological inhibition of γ-secretase and Notch signaling with DAPT normalizes depressive behavior, reduces corticosterone release, attenuates GR phosphorylation, and inhibits Notch2 signaling in PS2 MT mice. These findings identify Notch2 as a pivotal mediator linking chronic stress to molecular changes associated with depression and AD, and suggest that targeting Notch2 signaling may provide therapeutic benefits for comorbid mood and neurodegenerative disorders.
7.Evaluating Rituximab Failure Rates in Neuromyelitis Optica Spectrum Disorder: A Nationwide Real-World Study From South Korea
Su-Hyun KIM ; Ju-Hong MIN ; Sung-Min KIM ; Eun-Jae LEE ; Young-Min LIM ; Ha Young SHIN ; Young Nam KWON ; Eunhee SOHN ; Sooyoung KIM ; Min Su PARK ; Tai-Seung NAM ; Byeol-A YOON ; Jong Kuk KIM ; Kyong Jin SHIN ; Yoo Hwan KIM ; Jin Myoung SEOK ; Jeong Bin BONG ; Sohyeon KIM ; Hung Youl SEOK ; Sun-Young OH ; Ohyun KWON ; Sunyoung KIM ; Sukyoon LEE ; Nam-Hee KIM ; Eun Bin CHO ; Sa-Yoon KANG ; Seong-il OH ; Jong Seok BAE ; Suk-Won AHN ; Ki Hoon KIM ; You-Ri KANG ; Woohee JU ; Seung Ho CHOO ; Yeon Hak CHUNG ; Jae-Won HYUN ; Ho Jin KIM
Journal of Clinical Neurology 2025;21(2):131-136
Background:
and Purpose Treatments for neuromyelitis optica spectrum disorder (NMOSD) such as eculizumab, ravulizumab, satralizumab, and inebilizumab have significantly advanced relapse prevention, but they remain expensive. Rituximab is an off-label yet popular alternative that offers a cost-effective solution, but its real-world efficacy needs better quantification for guiding the application of newer approved NMOSD treatments (ANTs). This study aimed to determine real-world rituximab failure rates to anticipate the demand for ANTs and aid in resource allocation.
Methods:
We conducted a nationwide retrospective study involving 605 aquaporin-4-antibody-positive NMOSD patients from 22 centers in South Korea that assessed the efficacy and safety of rituximab over a median follow-up of 47 months.
Results:
The 605 patients treated with rituximab included 525 (87%) who received continuous therapy throughout the follow-up period (median=47 months, interquartile range=15–87 months). During this period, 117 patients (19%) experienced at least 1 relapse. Notably, 68 of these patients (11% of the total cohort) experienced multiple relapses or at least 1 severe relapse.Additionally, 2% of the patients discontinued rituximab due to adverse events, which included severe infusion reactions, neutropenia, and infections.
Conclusions
This study has confirmed the efficacy of rituximab in treating NMOSD, as evidenced by an 87% continuation rate among patients over a 4-year follow-up period. Nevertheless, the occurrence of at least one relapse in 19% of the cohort, including 11% who experienced multiple or severe relapses, and a 2% discontinuation rate due to adverse events highlight the urgent need for alternative therapeutic options.
8.Clinical practice guidelines for cervical cancer: an update of the Korean Society of Gynecologic Oncology Guidelines
Ji Geun YOO ; Sung Jong LEE ; Eun Ji NAM ; Jae Hong NO ; Jeong Yeol PARK ; Jae Yun SONG ; So-Jin SHIN ; Bo Seong YUN ; Sung Taek PARK ; San-Hui LEE ; Dong Hoon SUH ; Yong Beom KIM ; Keun Ho LEE
Journal of Gynecologic Oncology 2025;36(1):e70-
We describe the updated Korean Society of Gynecologic Oncology (KSGO) practice guideline for the management of cervical cancer, version 5.1. The KSGO announced the fifth version of its clinical practice guidelines for the management of cervical cancer in March 2024. The selection of the key questions and the systematic reviews were based on data available up to December 2022. Between 2023 and 2024, substantial findings from large-scale clinical trials and new advancements in cervical cancer research remarkably emerged. Therefore, based on the existing version 5.0, we updated the guidelines with newly accumulated clinical data and added 4 new key questions reflecting the latest insights in the field of cervical cancer. For each question, recommendation was formulated with corresponding level of evidence and grade of recommendation, all established through expert consensus.

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