Background: We aimed to investigate the characteristics of pediatric ulcerative colitis (UC) at diagnosis in Korea. Methods: This was a multicenter, registry-based, inception cohort study conducted in Korea between 2021 and 2023. Children and adolescents newly diagnosed with UC < 18 years were included. Baseline clinicodemographics, results from laboratory, endoscopic exams, and Paris classification factors were collected, and associations between factors at diagnosis were investigated. Results: A total 205 patients with UC were included. Male-to-female ratio was 1.59:1, and the median age at diagnosis was 14.7 years (interquartile range 11.9–16.2). Disease extent of E1 comprised 12.2% (25/205), E2 24.9% (51/205), E3 11.2% (23/205), and E4 51.7% (106/205) of the patients. S1 comprised 13.7% (28/205) of the patients. The proportion of patients with a disease severity of S1 was significantly higher in patients with E4 compared to the other groups (E1: 0% vs. E2: 2% vs. E3: 0% vs. E4: 24.5%, P < 0.001). Significant differences between disease extent groups were also observed in Pediatric Ulcerative Colitis Activity Index (median 25 vs. 35 vs. 40 vs. 45, respectively, P < 0.001), hemoglobin (median 13.5 vs.13.2 vs. 11.6 vs. 11.4 g/dL, respectively, P < 0.001), platelet count (median 301 vs. 324 vs. 372 vs. 377 × 103 /μL, respectively, P = 0.001), C-reactive protein (median 0.05 vs. 0.10 vs. 0.17 vs. 0.38 mg/dL, respectively, P < 0.001), and Ulcerative Colitis Endoscopic Index of Severity (median 4 vs. 4 vs. 4 vs. 5, respectively, P = 0.006). No significant differences were observed in factors between groups divided according to sex and diagnosis age. Conclusion This study represents the largest multicenter pediatric inflammatory bowel disease cohort in Korea. Disease severity was associated with disease extent in pediatric patients with UC at diagnosis.

Background: We aimed to investigate the characteristics of pediatric ulcerative colitis (UC) at diagnosis in Korea. Methods: This was a multicenter, registry-based, inception cohort study conducted in Korea between 2021 and 2023. Children and adolescents newly diagnosed with UC < 18 years were included. Baseline clinicodemographics, results from laboratory, endoscopic exams, and Paris classification factors were collected, and associations between factors at diagnosis were investigated. Results: A total 205 patients with UC were included. Male-to-female ratio was 1.59:1, and the median age at diagnosis was 14.7 years (interquartile range 11.9–16.2). Disease extent of E1 comprised 12.2% (25/205), E2 24.9% (51/205), E3 11.2% (23/205), and E4 51.7% (106/205) of the patients. S1 comprised 13.7% (28/205) of the patients. The proportion of patients with a disease severity of S1 was significantly higher in patients with E4 compared to the other groups (E1: 0% vs. E2: 2% vs. E3: 0% vs. E4: 24.5%, P < 0.001). Significant differences between disease extent groups were also observed in Pediatric Ulcerative Colitis Activity Index (median 25 vs. 35 vs. 40 vs. 45, respectively, P < 0.001), hemoglobin (median 13.5 vs.13.2 vs. 11.6 vs. 11.4 g/dL, respectively, P < 0.001), platelet count (median 301 vs. 324 vs. 372 vs. 377 × 103 /μL, respectively, P = 0.001), C-reactive protein (median 0.05 vs. 0.10 vs. 0.17 vs. 0.38 mg/dL, respectively, P < 0.001), and Ulcerative Colitis Endoscopic Index of Severity (median 4 vs. 4 vs. 4 vs. 5, respectively, P = 0.006). No significant differences were observed in factors between groups divided according to sex and diagnosis age. Conclusion This study represents the largest multicenter pediatric inflammatory bowel disease cohort in Korea. Disease severity was associated with disease extent in pediatric patients with UC at diagnosis.

Background: We aimed to investigate the characteristics of pediatric ulcerative colitis (UC) at diagnosis in Korea. Methods: This was a multicenter, registry-based, inception cohort study conducted in Korea between 2021 and 2023. Children and adolescents newly diagnosed with UC < 18 years were included. Baseline clinicodemographics, results from laboratory, endoscopic exams, and Paris classification factors were collected, and associations between factors at diagnosis were investigated. Results: A total 205 patients with UC were included. Male-to-female ratio was 1.59:1, and the median age at diagnosis was 14.7 years (interquartile range 11.9–16.2). Disease extent of E1 comprised 12.2% (25/205), E2 24.9% (51/205), E3 11.2% (23/205), and E4 51.7% (106/205) of the patients. S1 comprised 13.7% (28/205) of the patients. The proportion of patients with a disease severity of S1 was significantly higher in patients with E4 compared to the other groups (E1: 0% vs. E2: 2% vs. E3: 0% vs. E4: 24.5%, P < 0.001). Significant differences between disease extent groups were also observed in Pediatric Ulcerative Colitis Activity Index (median 25 vs. 35 vs. 40 vs. 45, respectively, P < 0.001), hemoglobin (median 13.5 vs.13.2 vs. 11.6 vs. 11.4 g/dL, respectively, P < 0.001), platelet count (median 301 vs. 324 vs. 372 vs. 377 × 103 /μL, respectively, P = 0.001), C-reactive protein (median 0.05 vs. 0.10 vs. 0.17 vs. 0.38 mg/dL, respectively, P < 0.001), and Ulcerative Colitis Endoscopic Index of Severity (median 4 vs. 4 vs. 4 vs. 5, respectively, P = 0.006). No significant differences were observed in factors between groups divided according to sex and diagnosis age. Conclusion This study represents the largest multicenter pediatric inflammatory bowel disease cohort in Korea. Disease severity was associated with disease extent in pediatric patients with UC at diagnosis.

Background: We aimed to investigate the characteristics of pediatric ulcerative colitis (UC) at diagnosis in Korea. Methods: This was a multicenter, registry-based, inception cohort study conducted in Korea between 2021 and 2023. Children and adolescents newly diagnosed with UC < 18 years were included. Baseline clinicodemographics, results from laboratory, endoscopic exams, and Paris classification factors were collected, and associations between factors at diagnosis were investigated. Results: A total 205 patients with UC were included. Male-to-female ratio was 1.59:1, and the median age at diagnosis was 14.7 years (interquartile range 11.9–16.2). Disease extent of E1 comprised 12.2% (25/205), E2 24.9% (51/205), E3 11.2% (23/205), and E4 51.7% (106/205) of the patients. S1 comprised 13.7% (28/205) of the patients. The proportion of patients with a disease severity of S1 was significantly higher in patients with E4 compared to the other groups (E1: 0% vs. E2: 2% vs. E3: 0% vs. E4: 24.5%, P < 0.001). Significant differences between disease extent groups were also observed in Pediatric Ulcerative Colitis Activity Index (median 25 vs. 35 vs. 40 vs. 45, respectively, P < 0.001), hemoglobin (median 13.5 vs.13.2 vs. 11.6 vs. 11.4 g/dL, respectively, P < 0.001), platelet count (median 301 vs. 324 vs. 372 vs. 377 × 103 /μL, respectively, P = 0.001), C-reactive protein (median 0.05 vs. 0.10 vs. 0.17 vs. 0.38 mg/dL, respectively, P < 0.001), and Ulcerative Colitis Endoscopic Index of Severity (median 4 vs. 4 vs. 4 vs. 5, respectively, P = 0.006). No significant differences were observed in factors between groups divided according to sex and diagnosis age. Conclusion This study represents the largest multicenter pediatric inflammatory bowel disease cohort in Korea. Disease severity was associated with disease extent in pediatric patients with UC at diagnosis.

Purpose: This study aimed to describe adult living donor liver transplantation (LDLT) for acute liver failure and evaluate its clinical significance by comparing its surgical and survival outcomes with those of deceased donor liver transplantation (DDLT). Methods: We retrospectively reviewed the medical records of 267 consecutive patients (161 LDLT recipients and 106 DDLT recipients) aged 18 years or older who underwent liver transplantation between January 2006 and December 2020. Results: The mean periods from hepatic encephalopathy to liver transplantation were 5.85 days and 8.35 days for LDLT and DDLT, respectively (P = 0.091). Among these patients, 121 (45.3%) had grade III or IV hepatic encephalopathy (living, 34.8% vs. deceased, 61.3%; P < 0.001), and 38 (14.2%) had brain edema (living, 16.1% vs. deceased, 11.3%; P = 0.269) before liver transplantation. There were no significant differences in in-hospital mortality (living, 11.8% vs. deceased, 15.1%; P = 0.435), 10-year overall survival (living, 90.8% vs. deceased, 84.0%; P = 0.096), and graft survival (living, 83.5% vs. deceased, 71.3%;P = 0.051). However, postoperatively, the mean intensive care unit stay was shorter in the LDLT group (5.0 days vs. 9.5 days, P < 0.001). In-hospital mortality was associated with vasopressor use (odds ratio [OR], 3.40; 95% confidence interval [CI], 1.45–7.96; P = 0.005) and brain edema (OR, 2.75; 95% CI, 1.16–6.52; P = 0.022) of recipient at the time of transplantation. However, LDLT (OR, 1.26; 95% CI, 0.59–2.66; P = 0.553) was not independently associated with in-hospital mortality. Conclusion LDLT is feasible for acute liver failure when organs from deceased donors are not available.

Purpose: When splitting a liver for adult and pediatric graft recipients, the retained left medial section (S4) will undergo ischemic necrosis and the right trisection graft becomes an extended right liver (ERL) graft. We investigated the fates of the retained S4 and its prognostic impact in adult split liver transplantation (SLT) using an ERL graft. Methods: This was a retrospective analysis of 25 adult SLT recipients who received split ERL grafts. Results: The mean model for end-stage liver disease (MELD) score was 27.3 ± 10.9 and graft-recipient weight ratio (GRWR) was 1.98 ± 0.44. The mean donor age was 26.5 ± 7.7 years. The split ERL graft weight was 1,181.5 ± 252.8 g, which resulted in a mean GRWR of 1.98 ± 0.44. Computed tomography of the retained S4 parenchyma revealed small ischemic necrosis in 16 patients (64.0%) and large ischemic necrosis in the remaining 9 patients (36.0%). No S4-associated biliary complications were developed. The mean GRWR was 1.87 ± 0.43 in the 9 patients with large ischemic necrosis and 2.10 ± 0.44 in the 15 cases with small ischemic necrosis (P = 0.283). The retained S4 parenchyma showed gradual atrophy on follow-up imaging studies. The amount of S4 ischemic necrosis was not associated with graft (P = 0.592) or patient (P = 0.243) survival. A MELD score of >30 and pretransplant ventilator support were associated with inferior outcomes. Conclusion The amount of S4 ischemic necrosis is not a prognostic factor in adult SLT recipients, probably due to a sufficiently large GRWR.

Purpose: Epithelioid hemangioendothelioma (EHE) is a rare borderline vascular tumor. This retrospective, single-center study evaluated the outcomes of hepatic resection (HR) in patients with hepatic EHE. Methods: Over the 10-year period from 2009 to 2018, 11 patients with hepatic EHE underwent HR, accounting for 0.1% of the 11,979 adults who underwent HR at our center. Diagnosis of hepatic EHE was confirmed by immunohistochemical staining for CD34, CD31, and factor VIII-related antigen. Results: The 11 patients included 9 females (81.8%) and 2 males (18.2%) with mean age of 43.5 ± 13.6 years. Preoperative imaging resulted in a preliminary diagnosis of suspected liver metastasis or EHE, with 9 patients (81.8%) undergoing liver biopsy. No patient presented with abnormally elevated concentrations of liver tumor markers. The extents of HR were determined by tumor size and location from trisectionectomy to partial hepatectomy. All patients recovered uneventfully from HR. Five patients showed tumor recurrence, with 4 receiving locoregional treatments for recurrent lesions. The 1-, 3-and 5-year disease-free survival rates were 90.9%, 54.5%, and 54.5%, respectively. Currently, all patients remain alive and are doing well. Univariate analysis on tumor recurrence showed that tumor size ≥ 4 cm was significantly associated with tumor recurrence (P = 0.032), but tumor number ≥ 4 was not related to (P = 0.24). Conclusion Hepatic EHE is a rare form of primary liver tumor often misdiagnosed as a metastatic tumor. Because of its malignant potential, HR is indicated if possible. HR plus, when necessary, treatment of recurrence yields favorable overall survival rates in patients with hepatic EHE.

Purpose: The incidence of human papillomavirus (HPV)-related oropharyngeal cancer (OPC) has increased, and staging and optimal therapeutic approaches are challenging. A questionnaire survey was conducted to investigate the controversial treatment policy of stage T2 OPC according to the N category and determine the opinions of multidisciplinary experts in Korea. Materials and Methods: Five OPC scenarios were developed by the Subcommittee on Oropharyngeal Treatment Guidelines of the Korean Society for Head and Neck Oncology and distributed to experts of multidisciplinary treatment hospitals. Results: Sixty-five experts from 45 institutions responded. For the HPV-positive T2N0M0 scenario, 67.7% of respondents selected surgery followed by definitive concurrent chemoradiotherapy (CCRT) or radiotherapy alone. For the T2N1M0 HPV-positive scenario, there was a notable difference in the selection of primary treatment by expert specialty; 53.9% of respondents selected surgery and 39.8% selected definitive CCRT as the primary treatment. For the T2N3M0 advanced HPV-positive scenario, 50.0% of respondents selected CCRT and 33.3% considered induction chemotherapy (IC) as the primary treatment. CCRT and IC were significantly more frequently selected for the HPV-related OPC cases (p=0.010). The interdepartmental variability showed that the head and neck surgeons and medical oncologists favored surgery, whereas the radiation oncologists preferably selected definitive CCRT (p < 0.001). Conclusion In this study, surgery was preferred for lymph node-negative OPC, and as lymph node metastasis progressed, CCRT tended to be preferred, and IC was administered. Clinical practice patterns by stage and HPV status showed differences according to expert specialty. Multidisciplinary consensus guidelines will be essential in the future.

Purpose: When splitting a liver for adult and pediatric graft recipients, the retained left medial section (S4) will undergo ischemic necrosis and the right trisection graft becomes an extended right liver (ERL) graft. We investigated the fates of the retained S4 and its prognostic impact in adult split liver transplantation (SLT) using an ERL graft. Methods: This was a retrospective analysis of 25 adult SLT recipients who received split ERL grafts. Results: The mean model for end-stage liver disease (MELD) score was 27.3 ± 10.9 and graft-recipient weight ratio (GRWR) was 1.98 ± 0.44. The mean donor age was 26.5 ± 7.7 years. The split ERL graft weight was 1,181.5 ± 252.8 g, which resulted in a mean GRWR of 1.98 ± 0.44. Computed tomography of the retained S4 parenchyma revealed small ischemic necrosis in 16 patients (64.0%) and large ischemic necrosis in the remaining 9 patients (36.0%). No S4-associated biliary complications were developed. The mean GRWR was 1.87 ± 0.43 in the 9 patients with large ischemic necrosis and 2.10 ± 0.44 in the 15 cases with small ischemic necrosis (P = 0.283). The retained S4 parenchyma showed gradual atrophy on follow-up imaging studies. The amount of S4 ischemic necrosis was not associated with graft (P = 0.592) or patient (P = 0.243) survival. A MELD score of >30 and pretransplant ventilator support were associated with inferior outcomes. Conclusion The amount of S4 ischemic necrosis is not a prognostic factor in adult SLT recipients, probably due to a sufficiently large GRWR.

BACKGROUND: Hepatocellular carcinoma (HCC) recurrence and development of de novo malignancy (DNM) after liver transplantation (LT) are the major causes of late recipient death.METHODS: We analyzed the incidence of extrahepatic DNM following living donor LT according to the status of pretransplant hepatic malignancy. We selected 2,076 adult patients who underwent primary LDLT during 7 years from January 2010 to December 2016.RESULTS: The pretransplant hepatic malignancy group (n = 1,012) showed 45 cases (4.4%) of the following extrahepatic DNMs: posttransplant lymphoproliferative disease (PTLD) in 10; lung cancer in 10; stomach cancer in 6; colorectal cancer in 5; urinary bladder cancer in 3; and other cancers in 11. The pretransplant no hepatic malignancy group (n = 1,064) showed 25 cases (2.3%) of the following extrahepatic DNMs: colorectal cancer in 3; stomach cancer in 3; leukemia in 3; lung cancer in 3; PTLD in 2; prostate cancer in 2; and other cancers in 9. Incidences of extrahepatic DNM in the pretransplant hepatic malignancy and no hepatic malignancy groups were as follows: 1.1% and 0.5% at 1 year, 3.2% and 2.0% at 3 years, 4.6% and 2.5% at 5 years, and 5.4% and 2.8% at 8 years, respectively (P = 0.006). Their overall patient survival rates were as follows: 97.3% and 97.2% at 1 year, 91.6% and 95.9% at 3 years, 89.8% and 95.4% at 5 years, and 89.2% and 95.4% at 8 years, respectively (P < 0.001). Pretransplant hepatic malignancy was the only significant risk factor for posttransplant extrahepatic DNM.CONCLUSION: Our results suggest that patients who had pretransplant hepatic malignancy be followed up more strictly because they have a potential risk of primary hepatic malignancy recurrence as well as a higher risk of extrahepatic DNM than patients without pretransplant hepatic malignancy.