1.Misinterpreted Recurrence of Autoimmune Pancreatitis as Malignant Transformation of Branch-Duct Intraductal Papillary Mucinous Neoplasm
Eun Jeong KIM ; Chang Hyun KIM ; Tae Seung LEE ; Jin Ho CHOI ; In Rae CHO ; Sang Hyub LEE ; Ji Kon RYU ; Woo Hyun PAIK
Korean Journal of Pancreas and Biliary Tract 2026;31(1):13-18
This case describes a male with a history of type 1 autoimmune pancreatitis (AIP) who had a concomitant branch-duct intraductal papillary mucinous neoplasm under long-term surveillance. During follow-up, new high-risk radiologic features developed within the pancreatic cyst, raising concern for malignant transformation and ultimately leading to surgical resection. However, final histopathologic examination revealed recurrent type 1 AIP rather than malignant progression of branch-duct intraductal papillary mucinous neoplasm, a finding that represents an uncommon and diagnostically challenging manifestation. This case suggests that when new imaging changes are observed during surveillance of pancreatic cystic lesions, clinicians should consider not only malignant transformation but also the possibility of recurrence or coexistence of underlying diseases such as AIP.
2.Erratum: Guidelines for the Use of Botulinum Toxin in Otolaryngology From the Korean Society of Laryngology, Phoniatrics and Logopedics Guideline Task Force
; Myung Jin BAN ; Chang Hwan RYU ; Joo Hyun WOO ; Young Chan LEE ; Dong Kun LEE ; Minsu KWON ; Yong Tae HONG ; Gil Joon LEE ; Hyung Kwon BYEON ; Seung Ho CHOI ; Seung Won LEE
Clinical and Experimental Otorhinolaryngology 2026;19(2):209-209
3.Biomimetic Architectural Cover Accelerates `Osseointegration of Titanium Implants
Su-Jin KIM ; Eun Chae KIM ; Weon-Young CHOI ; Seung-Jae LEE ; Je-Hwang RYU
Journal of Bone Metabolism 2026;33(1):30-39
Background:
Although various surface modifications enhance titanium (Ti) implant osseointegration, achieving rapid bone formation comparable to native healing remains challenging. Current strategies primarily focus on micro-scale topography, often overlooking the critical role of macroscopic three-dimensional (3D) architecture in osteoconduction.
Methods:
We hypothesized that mimicking native bone’s porous architecture is key to accelerating osseointegration. First, we verified the impact of structural continuity by comparing standard Ti implants with decellularized bone grafts in a mouse calvaria defect model. Subsequently, we developed a biomimetic polycaprolactone (PCL)-based 3D architectural cover (Cover-type) and evaluated its osseointegration efficacy in a rat femur model against conventional Ti implants.
Results:
The mouse study confirmed that decellularized bone integrated significantly faster than Ti, highlighting the necessity of 3D continuity. In the rat model, micro-computed tomography analysis indicated a clear trend of increased bone formation in the Cover-type group, though statistical significance was limited by sample size. However, histological analysis confirmed a statistically significant enhancement in bone-to-implant contact compared to controls (P<0.05). The PCL structure served as a scaffold for cell migration, effectively bridging the implant-bone gap.
Conclusions
These findings suggest that providing a bone-like 3D environment via a PCL cover may enhance histological osseointegration, rather than relying solely on surface chemistry.
4.Ethnic Heterogeneity in Reproductive Risk Factors for Breast Cancer, With a Focus on Asian Populations:A Meta-analysis
Youjin HONG ; Soseul SUNG ; Woojin LIM ; Sungji MOON ; Kwang-Pil KO ; Jung Eun LEE ; Inah KIM ; Sun Ha JEE ; Sun-Seog KWEON ; Min-Ho SHIN ; Sangmin PARK ; Seung-Ho RYU ; Sun Young YANG ; Jeongseon KIM ; Sang-Wook YI ; Sue K. PARK
Journal of Cancer Prevention 2026;31(1):20-27
suggest that some reproductive factors associated with BC differ across ethnicities and time trends, perhaps due to the prevalence of reproductive factors and the baseline hazard of BC.
5.Predictive factors of adolescents’ happiness: a random forest analysis of the 2023 Korea Youth Risk Behavior Survey
Eun Joo KIM ; Seong Kwang KIM ; Seung Hye JUNG ; Yo Seop RYU
Child Health Nursing Research 2025;31(2):85-95
Purpose:
This study aimed to identify predictive factors affecting adolescents’ subjective happiness using data from the 2023 Korea Youth Risk Behavior Survey. A random forest model was applied to determine the strongest predictive factors, and its predictive performance was compared with traditional regression models.
Methods:
Responses from a total of 44,320 students from grades 7 to 12 were analyzed. Data pre-processing involved handling missing values and selecting variables to construct an optimal dataset. The random forest model was employed for prediction, and SHAP (Shapley Additive Explanations) analysis was used to assess variable importance.
Results:
The random forest model demonstrated a stable predictive performance, with an R2 of .37. Mental and physical health factors were found to significantly affect subjective happiness. Adolescents’ subjective happiness was most strongly influenced by perceived stress, perceived health, experiences of loneliness, generalized anxiety disorder, suicidal ideation, economic status, fatigue recovery from sleep, and academic performance.
Conclusion
This study highlights the utility of machine learning in identifying factors influencing adolescents’ subjective happiness, addressing limitations of traditional regression approaches. These findings underscore the need for multidimensional interventions to improve mental and physical health, reduce stress and loneliness, and provide integrated support from schools and communities to enhance adolescents’ subjective happiness.
7.Adverse impact of metabolic dysfunction on fibrosis regression following direct-acting antiviral therapy: A multicenter study for chronic hepatitis C
Tom RYU ; Young CHANG ; Soung Won JEONG ; Jeong-Ju YOO ; Sae Hwan LEE ; Sang Gyune KIM ; Young Seok KIM ; Hong Soo KIM ; Seung Up KIM ; Jae Young JANG
Clinical and Molecular Hepatology 2025;31(2):548-562
Background/Aims:
Direct-acting antivirals (DAAs) effectively eradicate hepatitis C virus. This study investigated whether metabolic dysfunction influences the likelihood of fibrosis regression after DAA treatment in patients with chronic hepatitis C (CHC).
Methods:
This multicenter, retrospective study included 8,819 patients diagnosed with CHC who were treated with DAAs and achieved a sustained virological response (SVR) between January 2014 and December 2022. Fibrosis regression was defined as a 20% reduction in noninvasive surrogates for liver fibrosis, such as liver stiffness (LS) measured by vibration-controlled transient elastography (VCTE) and the fibrosis-4 (FIB-4) score. Hypercholesterolemia (h-TC) was defined as >200 mg/dL.
Results:
The median age of the study population was 59.6 years, with a predominance of male patients (n=4,713, 57.3%). Genotypes 1, 2, and others were confirmed in 3,872 (46.2%), 3,487 (41.6%), and 1,024 (12.2%) patients, respectively. Diabetes mellitus (DM) was present in 1,442 (17.2%) patients and the median LS was 7.50 kPa (interquartile range, 5.30–12.50). Multivariate analysis revealed that the presence of DM and pre-DAA h-TC were independently associated with a decreased probability of fibrosis regression by VCTE. Additionally, pre-DAA h-TC was independently associated with a decreased probability of fibrosis regression by the FIB-4.
Conclusions
Metabolic dysfunction has an unfavorable influence on fibrosis regression in patients with CHC who achieve SVR after DAA treatment.
8.The Incidence of Occult Malignancy in Contralateral Risk Reducing Mastectomy Among Affected Breast Cancer Gene Mutation Carriers in South Korea
Cho Eun LEE ; Dong Seung SHIN ; Ki Jo KIM ; Seok Jin NAM ; Seok Won KIM ; Jonghan YU ; Byung Joo CHAE ; Se Kyung LEE ; Jai Min RYU ; Goo-Hyun MUN ; Jai-Kyong PYON ; Byung-Joon JEON ; Kyongje WOO ; Jeong Eon LEE
Journal of Breast Cancer 2025;28(1):1-10
Purpose:
Breast cancer gene (BRCA) mutation is a well-known risk factor for breast cancer, and clinical interest in prophylactic mastectomy has increased in recent years.We investigated patients who were BRCA mutation carriers and underwent contralateral risk-reducing mastectomy (RRM), focusing on the incidence of occult malignancy after contralateral RRM.
Methods:
Prospectively collected data of patients with breast cancer treated at a single institution were retrospectively reviewed. Patients who underwent RRM with BRCA mutation who underwent RRM between January 2010 and November 2023 were included in this study.Among patients who underwent contralateral RRM, those with a primary cancer diagnosis were included, and those with occult malignancy on the contralateral RRM side were reviewed additionally. The demographics and pathologies of both primary breast cancer and occult malignancies were evaluated.
Results:
In our institution, 925 patients were identified as BRCA mutation carriers, and 320 patients underwent contralateral RRM along with primary breast cancer surgery. BRCA2 mutation occurred more frequently (54.8%) in the overall BRCA mutation cohort. Furthermore, we reviewed 320 patients diagnosed with breast cancer and detected as BRCA mutation carriers who underwent contralateral RRM; high proportion of them were BRCA1 mutation carriers.Interestingly, we found a low incidence of only seven patients (2.2%) with occult malignancy on contralateral RRM side, which is different from that reported in other nations.
Conclusion
The incidence of occult malignancy in the contralateral breast of breast cancer patients with breast cancer with BRCA mutation is significantly low, and may be influenced by several factors. Increased utilization of screening and advancements in diagnostic technologies in South Korea have reduced the chance of occult malignancy in RRM, and a variety of pathologic examination methods may affect the rate of incidence.
9.Prediction of Hemifacial Spasm Re-Appearing Phenomenon after Microvascular Decompression Surgery in Patients with Hemifacial Spasm Using Dynamic Susceptibility Contrast Perfusion Magnetic Resonance Imaging
Seung Hoon LIM ; Xiao-Yi GUO ; Hyug-Gi KIM ; Hak Cheol KO ; Soonchan PARK ; Chang-Woo RYU ; Geon-Ho JAHNG
Journal of Korean Neurosurgical Society 2025;68(1):46-59
Objective:
: Hemifacial spasm (HFS) is treated by a surgical procedure called microvascular decompression (MVD). However, HFS re-appearing phenomenon after surgery, presenting as early recurrence, is experienced by some patients after MVD. Dynamic susceptibility contrast (DSC) perfusion magnetic resonance imaging (MRI) and two analytical methods : receiver operating characteristic (ROC) curve and machine learning, were used to predict early recurrence in this study.
Methods:
: This study enrolled 60 patients who underwent MVD for HFS. They were divided into two groups : group A consisted of 32 patients who had early recurrence and group B consisted of 28 patients who had no early recurrence of HFS. DSC perfusion MRI was undergone by all patients before the surgery to obtain the several parameters. ROC curve and machine learning methods were used to predict early recurrence using these parameters.
Results:
: Group A had significantly lower relative cerebral blood flow than group B in most of the selected brain regions, as shown by the region-of-interest-based analysis. By combining three extraction fraction (EF) values at middle temporal gyrus, posterior cingulate, and brainstem, with age, using naive Bayes machine learning method, the best prediction model for early recurrence was obtained. This model had an area under the curve value of 0.845.
Conclusion
: By combining EF values with age or sex using machine learning methods, DSC perfusion MRI can be used to predict early recurrence before MVD surgery. This may help neurosurgeons to identify patients who are at risk of HFS recurrence and provide appropriate postoperative care.

Result Analysis
Print
Save
E-mail