1.Epidemiology of Gastric Cancer in Korea (1999–2022): Incidence, Survival, and 5-Year Conditional Relative Survival
Ki Bum PARK ; Mee Joo KANG ; Johyun HA ; Eun Hye PARK ; E Hwa YUN ; Hye-Jin KIM ; Kyu-Won JUNG ; Han Hong LEE
Journal of Gastric Cancer 2026;26(1):4-15
Purpose:
This study evaluated long-term trends in gastric cancer epidemiology and survival with a focus on conditional relative survival (CRS).
Materials and Methods:
Using the Korea Central Cancer Registry, we analyzed 665,184 patients who were newly diagnosed with gastric cancer between 1999 and 2022.The study period was divided into four intervals: Period I (1999–2005), Period II (2006–2011), Period III (2012–2017), and Period IV (2018–2022). Temporal trends in the incidence and mortality were assessed using crude and age-standardized rates. Relative survival was estimated using the Ederer II method, and the 5-year CRS was calculated according to the survival duration after diagnosis.
Results:
The incidence of gastric cancer increased until 2011 and subsequently declined, with a marked decrease observed in 2020. Individuals aged ≥70 years consistently had the highest incidence rates. Mortality rates showed a sustained decline throughout the study period. The overall 5-year relative survival improved from 69.8% in Period II to 78.4% in Period IV. The 5-year CRS increased from 86.1% at 1 year after diagnosis to 96.3% at 5 years.Patients with localized stage maintained a 5-year CRS above 95% at 1 year after diagnosis, whereas those with regional and distant stages showed 5-year CRS that consistently remained below 95%.
Conclusions
The incidence and mortality rates of gastric cancer in Korea have declined over the past two decades, accompanied by improved survival outcomes. The CRS analysis suggests that long-term follow-up is warranted, with the optimal duration varying according to patient characteristics.
2.Detection Ability of Quality of Life Changes and Responsiveness of the KOQUSS-40 and the EORTC QLQ-C30/STO22 in Patients Who Underwent Gastrectomy: A Prospective Comparative Study
Bang Wool EOM ; Keun Won RYU ; Ji Yeong AN ; Yun-Suhk SUH ; In CHO ; Sung Geun KIM ; Ji-Ho PARK ; Hoon HUR ; Hyung-Ho KIM ; Sang-Hoon AHN ; Sun-Hwi HWANG ; Hong Man YOON ; Ki Bum PARK ; Hyoung-Il KIM ; In-Gyu KWON ; Han-Kwang YANG ; Byoung-Jo SUH ; Sang-Ho JEONG ; Tae-Han KIM ; Oh Kyoung KWON ; Hye-Seong AHN ; Ji Yeon PARK ; Ki Young YOON ; Myoung Won SON ; Seong-Ho KONG ; Young-Gil SON ; Geum Jong SONG ; Jong Hyuk YUN ; Jung-Min BAE ; Do Joong PARK ; Sol LEE ; Jun-Young YANG ; Kyung Won SEO ; You-Jin JANG ; So Hyun KANG ; Joongyub LEE ; Hyuk-Joon LEE ;
Cancer Research and Treatment 2026;58(1):221-231
Purpose:
The aim of this study is to compare the detection ability of quality of life (QoL) changes and responsiveness of the KOrean QUality of life in Stomach cancer patients Study group (KOQUSS)-40 and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ).
Materials and Methods:
A multicenter prospective observational study was conducted to evaluate QoL changes after various gastrectomies between January 2021 and April 2022. Participants were instructed to complete the KOQUSS-40 and EORTC QLQ-C30/STO22 preoperatively and at 1, 3, 6, and 12 months postoperatively. QoL changes over time and QoL responsiveness were assessed for each questionnaire.
Results:
Data from 491 patients who underwent curative gastrectomy for gastric cancer at 22 institutions were analyzed. The summary scores of the KOQUSS-40 and EORTC QLQ-STO22 showed significant differences between the total and proximal gastrectomy groups (p=0.044 and p=0.038, respectively), but no difference was observed for the EORTC QLQ-C30. Dysphagia on the KOQUSS-40 was significantly different between the total and proximal gastrectomy groups (p=0.031); however, dysphagia on the EORTC QLQ-STO22 did not differ. The responsiveness of the KOQUSS-40 was similar to that of the EORTC QLQ in patients who experienced ≥ 10% body weight loss, but approximately 10% less in patients receiving adjuvant chemotherapy than the EORTC QLQ.
Conclusion
KOQUSS-40 has several advantages over EORTC QLQ-C30/STO22 when comparing QoL between the total and proximal gastrectomy groups. The findings provide information for researchers investigating the QoL of patients who have undergone curative gastrectomy for gastric cancer.
3.A Case of Rheumatoid Neutrophilic Dermatitis with an Atypical Presentation
Ik Seon CHOI ; Seong Hee CHOI ; Ki Bum MYUNG ; Jee Hyun KANG ; Seung Hyun CHEONG
Korean Journal of Dermatology 2026;64(1):28-32
Rheumatoid neutrophilic dermatitis (RND) is a rare extra-articular skin lesion associated with rheumatoid arthritis (RA). Lesions typically occur symmetrically on the extensor surfaces of the extremities and present with variable clinical features. A 78-year-old female with a 2-month history of skin rash on the right forearm and left lower leg, with no other systemic symptoms, visited the dermatology department of our hospital. She had been diagnosed with seropositive RA approximately 20 years ago. The skin rash was asymmetrically distributed and presented with localized pustules, purpura, and edema. The biopsy specimen showed dermal infiltration by neutrophils, leukocytoclasia without vasculitis, and a neutrophilic dermal abscess. No fungi or bacteria were detected on any of the stains. The patient was diagnosed with RND. Clinical improvement was noted after treatment with dapsone, followed by colchicine and methylprednisolone. In this case report, we described the case of a female patient with atypically presented RND and conducted a literature review.
4.Bariatric surgery for treatment of morbid obesity in adults
The Korean Journal of Internal Medicine 2025;40(1):24-39
Morbid obesity requires active intervention, with treatment options including lifestyle modification, pharmacotherapy, and surgery. As the prevalence of obesity continues to rise in Korea, it is crucial for specialists and general practitioners to have a comprehensive understanding of obesity and its management. Bariatric surgery is the most effective treatment modality for obesity, leading to significant weight loss and metabolic benefits. It involves surgical alterations of normal anatomical structures to improve overall health. Therefore, selecting the appropriate procedure based on the individual characteristics of patients is crucial. This review highlights the two most commonly performed bariatric procedures worldwide, including in Korea: sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB). Furthermore, it provides a comprehensive overview of the surgical techniques involved in SG and RYGB, addresses potential complications, and presents findings from key studies on the weight loss and metabolic outcomes of these surgeries. Additionally, to support clinical application, the review provides outcome data for these procedures based on studies conducted in Korean populations. In addition to SG and RYGB, this review briefly introduces other surgical and endoscopic options, as well as pharmacological treatments that are currently available or may become viable options in the near future.
5.Predicting renal function using fundus photography: role of confounders
Hyun-Woong PARK ; Hae Ri KIM ; Ki Yup NAM ; Bum Jun KIM ; Taeseen KANG
The Korean Journal of Internal Medicine 2025;40(2):310-320
Background/Aims:
The kidneys and retina are highly vascularized organs that frequently exhibit shared pathologies, with nephropathy often associated with retinopathy. Previous studies have successfully predicted estimated glomerular filtration rates (eGFRs) using fundus photographs. We evaluated the performance of the Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formulas in eGFR prediction.
Methods:
We enrolled patients with fundus photographs and corresponding creatinine measurements taken on the same date. One photograph per eye was randomly selected, resulting in a final dataset of 45,108 patients (88,260 photographs). Data including sex, age, and blood creatinine levels were collected for eGFR calculation using the MDRD and CKD-EPI formulas. EfficientNet B3 models were used to predict each parameter.
Results:
Deep neural network models accurately predicted age and sex using fundus photographs. Sex was identified as a confounding variable in creatinine prediction. The MDRD formula was more susceptible to this confounding effect than the CKD-EPI formula. Notably, the CKD-EPI formula demonstrated superior performance compared to the MDRD formula (area under the curve 0.864 vs. 0.802).
Conclusions
Fundus photographs are a valuable tool for screening renal function using deep neural network models, demonstrating the role of noninvasive imaging in medical diagnostics. However, these models are susceptible to the influence of sex, a potential confounding factor. The CKD-EPI formula, less susceptible to sex bias, is recommended to obtain more reliable results.
6.Ulcerative colitis-associated colorectal neoplasm is increasing as a surgical indication in the biologics era:a retrospective observational study of 20 years of experience in a single tertiary center
Hyo Jun KIM ; Seung-Bum RYOO ; Jin Sun CHOI ; Han-Ki LIM ; Min Jung KIM ; Ji Won PARK ; Seung-Yong JEONG ; Kyu Joo PARK
Annals of Surgical Treatment and Research 2025;108(3):150-157
Purpose:
We aimed to identify changes in surgical indications in patients with ulcerative colitis (UC) in the biologics era in a single tertiary center.
Methods:
In this retrospective observational study, 108 patients with UC who underwent abdominal surgery for UC at Seoul National University Hospital from 2000 to 2021 were included. We compared the total number of patients undergoing UC before and after the introduction of biologic therapy.
Results:
Of the 108 patients with UC (male, 59 and female, 49; mean age, 46.8 years), 30 (27.8%) underwent surgery for neoplasms and 78 (72.2%) for medical intractability without neoplasms. The duration between diagnosis and surgery varied significantly (126.00 months vs. 60.50 months, P = 0.001). A significant difference was also noted in the surgical indications according to time (P = 0.02). Between 2000 and 2010, 12 patients (19.4%) underwent surgery for UC with neoplasms and 50 (80.6%) for UC without neoplasms, while between 2011 and 2021, 18 (39.1%) and 28 patients (60.9%) underwent surgery for UC with and without neoplasms, respectively.
Conclusion
Since 2011, when biological agents were covered by insurance in South Korea, there has been a relative increase in the incidence of surgical indications for neoplasia cases. Focusing on closely monitoring individuals with longterm UC for neoplasms is necessary.
7.Bariatric surgery for treatment of morbid obesity in adults
The Korean Journal of Internal Medicine 2025;40(1):24-39
Morbid obesity requires active intervention, with treatment options including lifestyle modification, pharmacotherapy, and surgery. As the prevalence of obesity continues to rise in Korea, it is crucial for specialists and general practitioners to have a comprehensive understanding of obesity and its management. Bariatric surgery is the most effective treatment modality for obesity, leading to significant weight loss and metabolic benefits. It involves surgical alterations of normal anatomical structures to improve overall health. Therefore, selecting the appropriate procedure based on the individual characteristics of patients is crucial. This review highlights the two most commonly performed bariatric procedures worldwide, including in Korea: sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB). Furthermore, it provides a comprehensive overview of the surgical techniques involved in SG and RYGB, addresses potential complications, and presents findings from key studies on the weight loss and metabolic outcomes of these surgeries. Additionally, to support clinical application, the review provides outcome data for these procedures based on studies conducted in Korean populations. In addition to SG and RYGB, this review briefly introduces other surgical and endoscopic options, as well as pharmacological treatments that are currently available or may become viable options in the near future.
8.Predicting renal function using fundus photography: role of confounders
Hyun-Woong PARK ; Hae Ri KIM ; Ki Yup NAM ; Bum Jun KIM ; Taeseen KANG
The Korean Journal of Internal Medicine 2025;40(2):310-320
Background/Aims:
The kidneys and retina are highly vascularized organs that frequently exhibit shared pathologies, with nephropathy often associated with retinopathy. Previous studies have successfully predicted estimated glomerular filtration rates (eGFRs) using fundus photographs. We evaluated the performance of the Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formulas in eGFR prediction.
Methods:
We enrolled patients with fundus photographs and corresponding creatinine measurements taken on the same date. One photograph per eye was randomly selected, resulting in a final dataset of 45,108 patients (88,260 photographs). Data including sex, age, and blood creatinine levels were collected for eGFR calculation using the MDRD and CKD-EPI formulas. EfficientNet B3 models were used to predict each parameter.
Results:
Deep neural network models accurately predicted age and sex using fundus photographs. Sex was identified as a confounding variable in creatinine prediction. The MDRD formula was more susceptible to this confounding effect than the CKD-EPI formula. Notably, the CKD-EPI formula demonstrated superior performance compared to the MDRD formula (area under the curve 0.864 vs. 0.802).
Conclusions
Fundus photographs are a valuable tool for screening renal function using deep neural network models, demonstrating the role of noninvasive imaging in medical diagnostics. However, these models are susceptible to the influence of sex, a potential confounding factor. The CKD-EPI formula, less susceptible to sex bias, is recommended to obtain more reliable results.
9.Clinical impact of drug-coated balloon treatment of coronary artery disease in elderly patients.
Eun-Seok SHIN ; Mi Hee JANG ; Sunwon KIM ; Dong Oh KANG ; Ki-Bum WON ; Bitna KIM ; Ae-Young HER
Journal of Geriatric Cardiology 2025;22(1):150-158
BACKGROUND:
Data on drug-coated balloon (DCB) treatment in elderly patients are limited. This study was to evaluate the efficacy of DCB treatment in percutaneous coronary intervention (PCI) among elderly patients.
METHODS:
A retrospective analysis included 232 patients aged 75 years or older with coronary artery disease who underwent successful PCI using either DCB alone or in combination with drug-eluting stent (DES) based on pre-dilation results (DCB-based PCI). These patients were compared with 1818 elderly patients who underwent second-generation DES implantation (DES-only PCI). The endpoint was major adverse cardiovascular events (MACE) at 2-year follow-up.
RESULTS:
In the DCB-based PCI, 61.2% of patients received DCB-only treatment. Compared to DES-only PCI, the DCB-based PCI group had fewer stents (0.5 ± 0.7 and 1.7 ± 0.8, P < 0.001), shorter stent lengths (13.3 ± 20.9 mm and 37.4 ± 23.0 mm, P < 0.001), and lower usage of small stents with a diameter of 2.5 mm or less (15.6% and 28.7%, P = 0.010). The DCB-based PCI group exhibited lower rate of MACE (5.5% and 13.1%, P = 0.003), target vessel revascularization (1.1% and 5.6%, P = 0.017) and major bleeding (0.7% and 5.1%, P = 0.009) at 2-year follow-up. The reduced risk in 2-year MACE was consistently observed across various matching procedures, with the most significant reduction noted in target vessel revascularization and major bleeding.
CONCLUSION
The DCB-based PCI reduced stent burden, particularly in the usage of small diameter stents, and was associated with lower risks of MACE, target vessel revascularization, and major bleeding compared to DES-only PCI in elderly patients.
10.Ulcerative colitis-associated colorectal neoplasm is increasing as a surgical indication in the biologics era:a retrospective observational study of 20 years of experience in a single tertiary center
Hyo Jun KIM ; Seung-Bum RYOO ; Jin Sun CHOI ; Han-Ki LIM ; Min Jung KIM ; Ji Won PARK ; Seung-Yong JEONG ; Kyu Joo PARK
Annals of Surgical Treatment and Research 2025;108(3):150-157
Purpose:
We aimed to identify changes in surgical indications in patients with ulcerative colitis (UC) in the biologics era in a single tertiary center.
Methods:
In this retrospective observational study, 108 patients with UC who underwent abdominal surgery for UC at Seoul National University Hospital from 2000 to 2021 were included. We compared the total number of patients undergoing UC before and after the introduction of biologic therapy.
Results:
Of the 108 patients with UC (male, 59 and female, 49; mean age, 46.8 years), 30 (27.8%) underwent surgery for neoplasms and 78 (72.2%) for medical intractability without neoplasms. The duration between diagnosis and surgery varied significantly (126.00 months vs. 60.50 months, P = 0.001). A significant difference was also noted in the surgical indications according to time (P = 0.02). Between 2000 and 2010, 12 patients (19.4%) underwent surgery for UC with neoplasms and 50 (80.6%) for UC without neoplasms, while between 2011 and 2021, 18 (39.1%) and 28 patients (60.9%) underwent surgery for UC with and without neoplasms, respectively.
Conclusion
Since 2011, when biological agents were covered by insurance in South Korea, there has been a relative increase in the incidence of surgical indications for neoplasia cases. Focusing on closely monitoring individuals with longterm UC for neoplasms is necessary.

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