Purpose: To describe the incidence and mortality of upper tract urothelial carcinoma (UTUC) from 2002–2020 using data from the Korean National Health Insurance Service, which contains data from the entire Korean population. Materials and Methods: Reimbursement records for 43,255 patients diagnosed with primary UTUC (according to the International Classification of Disease 10th revision code C65 and C66) between 2002–2020 were retrieved. The study period was split into four: period I (2002–2005), period II (2006–2010), period III (2011–2015), and period IV (2016–2020). Trends were quantified by calculating the annual percentage change (APC). Mortality data were obtained from the Statistics Korea. Results: From 2002–2020, the incidence of UTUC in Korea increased gradually from 9.34 to 11.40 per 100,000 person-years. Although there was a male predominance, the male to female ratio did not change significantly over time; however, age at the time of diagnosis, the comorbidity index, and the proportion of patients undergoing open/laparoscopic surgery increased significantly over time. There was a modest improvement in 5-year survival (both all cause- and cancer-specific) over the study period. Multivariate analysis identified age at diagnosis, sex, the comorbidity index, and open/laparoscopic surgery as being associated with survival. Conclusions Between 2002 and 2020, the incidence of UTUC in Korea showed a general upward trend; however, survival outcomes have improved. These representative datasets from the Korean population might provide crucial information that enables clinicians to better understand of the epidemiology of UTUC in Korea.

Purpose: Since the introduction of robotic surgery, robots for colorectal cancer have replaced laparoscopic surgery, and a single-port robot (SPR) platform has been launched and is being used to treat patients. We analyzed the learning curve and initial complications of using an SPR platform in colorectal cancer surgery. Methods: We reviewed 39 patients who underwent SPR colectomy from April to October 2019. All surgeries were performed by the same surgeon using an SPR device. A learning curve was generated using the cumulative sum methodology to assess changes in total operation time, docking time, and surgeon console time. We grouped the patients into 3 groups according to the time period: the first 11 were phase 1, the next 11 were phase 2, and the last 17 were phase 3. Results: The mean age of the patients was 61.28±13.03 years, and they had a mean body mass index of 23.79±2.86 kg/m2. Among the patients, 23 (59.0%) were male, and 16 (41.0%) were female. The average operation time was 186.59±51.30 minutes, the average surgeon console time was 95.49±35.33 minutes, and the average docking time (time from skin incision to robot docking) was 14.87±10.38 minutes. The surgeon console time differed significantly among the different phases (P<0.001). Complications occurred in 8 patients: 2 ileus, 2 postoperation hemoglobin changes, 3 urinary retentions, and 1 complicated fluid collection. Conclusion In our experience, the learning curve for SPR colectomy was achieved after the 18th case.

Background: Primary cicatricial alopecia (PCA) is a rare disease that causes irreversible destruction of hair follicles and affects the quality of life (QOL). Objective: We aimed to investigate the disease awareness, medical use behavior, QOL, and real-world diagnosis and treatment status of patients with PCA. Methods: A self-administered questionnaire was administered to patients with PCA and their dermatologists. Patients aged between 19 and 75 years who visited one of 27 dermatology departments between September 2021 and September 2022 were included. Results: In total, 274 patients were included. The male-to-female ratio was 1:1.47, with a mean age of 45.7 years. Patients with neutrophilic and mixed PCA were predominantly male and younger than those with lymphocytic PCA. Among patients with lymphocytic PCA, lichen planopilaris was the most common type, and among those with neutrophilic PCA, folliculitis decalvans was the most common type. Among the total patients, 28.8% were previously diagnosed with PCA, 47.0% were diagnosed with PCA at least 6 months after their first hospital visit, 20.0% received early treatment within 3 months of disease onset, and 54.4% received steady treatment. More than half of the patients had a moderate to severe impairment in QOL. Topical/intralesional steroid injections were the most common treatment. Systemic immunosuppressants were frequently prescribed to patients with lymphocytic PCA, and antibiotics were mostly prescribed to patients with neutrophilic PCA. Conclusion This study provides information on the disease awareness, medical use behavior, QOL, diagnosis, and treatment status of Korean patients with PCA. This can help dermatologists educate patients with PCA to understand the necessity for early diagnosis and steady treatment.

Background/Aims: The ursodeoxycholic acid (UDCA) response score (URS) was developed to identify poor responders to UDCA before treatment, in order to offer timely and proactive intervention. However, validation of the URS in Asian population is warranted. Methods: A total of 173 Asian patients diagnosed with primary biliary cholangitis (PBC) between 2007 and 2016 at seven academic institutions in Korea who started UDCA treatment were analyzed to validate the performance of URS. UDCA response was defined as an alkaline phosphatase level less than 1.67 times the upper limit of normal after 1-year of UDCA treatment. In addition, prognostic performance of URS for liver-related events, defined as newly developed hepatic decompensation or hepatocellular carcinoma was evaluated. Results: After 1 year of UDCA treatment, 133 patients (76.9%) achieved UDCA response. UDCAresponse rate was 98.7% for those with URS ≥1.41 (n=76) and 58.8% for those with URS <1.41(n=97). The area under the receiver operating characteristic curve of URS in predicting UDCAresponse was 0.84 (95% confidence interval, 0.78 to 0.88). During a median follow-up of 6.5years, liver-related events developed in 18 patients (10.4%). Among 117 patients with PBC stage I-III by histological evaluation, the 5-year liver-related event-free survival rate differed accordingto the URS; 100% for URS ≥1.41 and 86.5% for URS <1.41 (p=0.005). Conclusions URS demonstrated good performance in predicting a UDCA treatment response in Asian PBC patients. In addition, the risk of liver-related events differed according to the URS for the PBC stage. Thus, URS can be used to predict the response and clinical outcome in patients with PBC.

Background/Aims: This study aimed to investigate whether pretransplant frailty can predict postoperative morbidity and mortality after liver transplantation (LT) in patients with cirrhosis. Methods: We retrospectively reviewed 242 patients who underwent LT between 2018 and 2020 at a tertiary hospital in Korea. Results: Among them, 189 patients (78.1%) received LT from a living donor. Physical frailty at baseline was assessed by the Short Physical Performance Battery (SPPB), by which patientswere categorized into two groups: frail (SPPB <10) and non-frail (SPPB ≥10). Among the whole cohort (age, 55.0±9.2 years; male, 165 [68.2%]), 182 patients were classified as non-frail and 60 patients were classified as frail. Posttransplant survival was shorter in the frail group than the non-frail group (9.3 months vs 11.6 months). Postoperative intensive care unit stay was longer in the frail group than in the non-frail group (median, 6 days vs 4 days), and the 30-day complication rate was higher in the frail group than in the non-frail group (78.3% vs 59.3%). Frailty was an independent risk factor for posttransplant mortality (adjusted hazard ratio, 2.38; 95% confidence interval, 1.02 to 5.57). In subgroup analysis, frail patients showed lower posttransplant survival regardless of history of hepatocellular carcinoma and donor type. Conclusions Assessment of pretransplant frailty, as measured by SPPB, provides important prognostic information for clinical outcomes in cirrhotic patients undergoing LT.

Long-acting  2 -agonist (LABA)/long-acting muscarinic-antagonist (LAMA) dual therapy has been found to be more effective than LAMA monotherapy in the treatment of chronic obstructive pulmonary disease (COPD). However, among patients with group B or D COPD, the characteristics of patients for whom LABA/LAMA dual therapy is superior to LAMA monotherapy in minimizing acute exacerbations remain unknown.With data from a prospective COPD cohort, subgroup analyses were conducted to determine whether LABA/LAMA dual therapy was superior to LAMA monotherapy in reducing the rate of acute exacerbations in group B and D COPD patients. Group B and D COPD patients taking LAMA or LABA/LAMA were enrolled according to the 2022 Global initiative for Chronic Obstructive Pulmonary Disease guidelines. A total of 737 patients were included in this study: 600 with group B COPD and 137 with group D COPD. Compared with patients taking LAMA monotherapy, those taking LABA/ LAMA had a significantly lower incidence of acute exacerbations over 1 year. In the subgroup of patients ≥70 years old, there was a significantly lower risk of severe COPD exacerbations among group B patients taking LABA/LAMA than among those taking LAMA monotherapy (odds ratio [OR], 0.258; 95% confidence interval [CI], 0.095– 0.703). In contrast, in the subgroup of group D patients with COPD Assessment Test scores ≥25, compared with LAMA monotherapy, LABA/LAMA treatment was associated with lower risk of severe COPD exacerbations (OR, 0.115; 95% CI, 0.018-0.749).The combination of LABA and LAMA was found to be superior to LAMA monotherapy, especially for treating older adults with group B COPD, as well as for group D patients with severe symptoms.

Background: Brentuximab vedotin (BV), a potent antibody-drug conjugate, targets the CD30 antigen.In Korea, BV has been approved for the treatment of relapsed or refractory Hodgkin lymphoma (HL), anaplastic large-cell lymphoma (ALCL), and cutaneous T-cell lymphomas, including mycosis fungoides (MF). However, there are limited data reflecting real-world experiences with BV treatment for HL, ALCL, and MF. Methods: This was a multicenter, non-interventional registry study of the efficacy and safety of BV in patients with relapsed or refractory CD30-positive lymphoma (CISL1803/BRAVO).Outcomes were determined based on the occurrence of relapse or progression and overall survival after BV treatment. Results: A total of 85 patients were enrolled in this study. The median number of BV cycles was 10 (range, 2‒16) in the patients with HL. The objective response rate (ORR) of patients with HL to BV was 85.4% (41/48), comprising 27 complete responses (CRs) and 14 partial responses (PRs). The ORR of ALCL was 88% (22/25), consisting of 17 CRs and five PRs, whereas the ORR of MF was 92% (11/12). At the median follow-up of 44.6 months after BV treatment, the median post-BV progression-free survival of HL, ALCL, and MF patients was 23.6 months, 29.0 months, and 16.7 months, respectively (P =0.641). The most common side effect of BV was peripheral neuropathy; 22 patients (25.9%, 22/85) experienced peripheral neuropathy (all grades). Conclusion The treatment outcomes of patients with relapsed or refractory CD30-positive lymphoma improved with BV treatment, and the safety profile was manageable.

Changes in the prevalence of disease over time provide valuable information from a public health perspective. We used data from Korea Military Manpower Administration medical examinations for conscription between 2003 and 2019 (n = 5,355,941), which involved young men aged 19 years, to observe changes in liver disease over time at a population level. Trends in the prevalence of hepatitis B surface antigen (HBsAg), elevated alanine aminotransferase (ALT) levels, the fibrosis-4 (FIB-4) index, obesity, and hypertension were assessed. The prevalence of HBsAg steadily decreased from 3.19% for men born in 1984 to 0.18% for men born in 2000. Among HBsAg-negative subjects, the prevalence of elevated ALT levels increased from 13.15% for men born in 1986 to 16.48% for men born in 2000. The prevalence of obesity, hypertension and the proportion with high FIB-4 scores (≥ 1.45) also increased. This population-based nationwide analysis showed a decreasing trend of HBsAg and increasing trends of possible non-alcoholic fatty liver disease.

Recently, abdominoperineal resection (APR) using a robot has been demonstrated in other studies. However, there has been no report on APR for rectal cancer using the single-port robot (SPR) platform. In response to this research gap, we described the clinical experience of APR using a SPR. From April 2019 to March 2020, APR using a SPR platform was performed in a total of 4 patients. Three patients had a transumbilical approach, and 1 patient had a transstoma site approach. The average operation time was 307 minutes, and the patient docking time to the SPR platform was 133.5 minutes. There were no complications during the operation, and no laparoscopy or open conversion. No reoperation occurred within 30 days. Mild postoperative complications occurred in 2 patients. We found that APR has safety and feasibility in surgery using an SPR platform. There was no intraoperative event and severe postoperative complications.