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.

Purpose: There have been efforts to find alternative samples other than standard samples of tissue or plasma for mutational analyses for lung cancer patients. However, no other sample or technique has replaced the mutational analyses using standard samples. In this prospective study, we assessed a novel bronchoscopy method, named as targeted washing technique, for detecting the epidermal growth factor receptor (EGFR) mutation. Materials and Methods: A 3.0-mm ultrathin bronchoscope was precisely navigated to the target lung lesion with the assistance of virtual bronchoscopic navigation and fluoroscopy. Once the bronchoscope is placed in front of target lung lesion, 0.9% normal saline was instilled for targeted washing. EGFR testing using targeted washing fluid (TWF) was compared to standard methods using plasma or tumor tissue. Results: In 41 TWF samples, the T790M mutation was detected in tissue, plasma, and TWF samples at rates of 22.0%, 9.8%, and 29.3%, respectively. The overall EGFR T790M detection rate using tissue, plasma, or TWF samples was 36.6%, with TWF samples increasing the T790M mutation detection rate by up to 10%. The accuracy of T790M mutation detection using TWF sample was 82.9% compared with standard samples. Four patients were found to have the EGFR T790M mutation solely through EGFR testing using TWF, which repeated rebiopsies using either plasma or tissue finally confirmed to have the T790M mutation. Conclusion We demonstrated the clinical potential of targeted washing technique for molecular testing, which can be a good option to overcome spatial heterogeneity, low sensitivity of plasma sample or technical limitations in collecting tumor tissues.

The use of miniscrew-assisted rapid palatal expansion (MARPE) has yielded successful outcomes in late adolescence and early adulthood, particularly in correcting transverse maxillary discrepancies and enhancing airway expansion. This report presents three cases of children at different dentition stages treated with MARPE. In one patient with severe crowding, MARPE enabled dental alignment without the need for premolar extractions. Additionally, MARPE combined with facemask therapy improved the patient’s facial profile, resulting in high patient and guardian satisfaction. These cases highlight MARPE’s potential as an effective treatment for maxillary discrepancies and severe arch length discrepancies in children.

Background: and Purpose To determine the clinical phenotypes, relapse timing, treatment responses, and outcomes of children with relapsing myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). Methods: We collected the demographic, clinical, laboratory, and radiological data of patients aged <18 years who had been diagnosed with MOGAD at Seoul National University Children’s Hospital between January 2010 and January 2022; 100 were identified as positive for MOG antibodies, 43 of whom experienced relapse. Results: The median age at onset was 7 years (range 2–16 years). The median number of relapses was 2 (range 1–8), and patients were followed up for a median of 65 months (range 5–214 months). The first relapse was experienced before 3 months from onset by 15 patients (34.9%). The most-common initial phenotypes were acute disseminated encephalomyelitis (n=17, 39.5%) and optic neuritis (ON; n=11, 25.6%). The most-common relapse phenotypes were neuromyelitis optica spectrum disorder (n=9, 20.9%), relapsing ON (n=6, 14.0%), and multiphasic disseminated encephalomyelitis (n=6, 14.0%). Many of the patients (n=18, 41.9%) were not specifically categorized. A high proportion of these patients had non-acute disseminated encephalomyelitis encephalitis. Atypical phenotypes such as prolonged fever or hemiplegic migraine-like episodes were also noted. Mycophenolate mofetil and cyclic immunoglobulin treatment significantly reduced the annual relapse rates. Conclusions Our 43 pediatric patients with relapsing MOGAD showed a tendency toward early relapse and various relapse phenotypes. The overall prognoses of these patients were good regardless of phenotype or response to second-line immunosuppressant treatment.

Purpose: Since 1995, the Korean Gastric Cancer Association (KGCA) has been periodically conducting nationwide surveys on patients with surgically treated gastric cancer. This study details the results of the survey conducted in 2023. Materials and Methods: The survey was conducted from March to December 2024 using a standardized case report form. Data were collected on 86 items, including patient demographics, tumor characteristics, surgical procedures, and surgical outcomes. The results of the 2023 survey were compared with those of previous surveys. Results: Data from 12,751 cases were collected from 66 institutions. The mean patient age was 64.6 years, and the proportion of patients aged ≥71 years increased from 9.1% in 1995 to 31.7% in 2023. The proportion of upper-third tumors slightly decreased to 16.8% compared to 20.9% in 2019. Early gastric cancer accounted for 63.1% of cases in 2023.Regarding operative procedures, a totally laparoscopic approach was most frequently applied (63.2%) in 2023, while robotic gastrectomy steadily increased to 9.5% from 2.1% in 2014.The most common anastomotic method was the Billroth II procedure (48.8%) after distal gastrectomy and double-tract reconstruction (51.9%) after proximal gastrectomy in 2023.However, the proportion of esophago-gastrostomy with anti-reflux procedures increased to 30.9%. The rates of post-operative mortality and overall complications were 1.0% and 15.3%, respectively. Conclusions The results of the 2023 nationwide survey demonstrate the current status of gastric cancer treatment in Korea. This information will provide a basis for future gastric cancer research.

Purpose: Inotuzumab ozogamicin (INO) has demonstrated a safe bridging role to allogeneic hematopoietic stem cell transplantation (HSCT) in patients with relapsed or refractory B-cell acute lymphoblastic leukemia (R/R B-ALL). How‑ ever, hepatic veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is frequently observed. This study aimed to identify significant features of INO-associated VOD/SOS. Methods: We reviewed seven cases of hepatic VOD/SOS that developed either during INO salvage or after alloge‑ neic HSCT following INO-induced complete remission (CR). Diagnosis and severity grading of VOD/SOS were based on the revised criteria from the European Society for Blood and Marrow Transplantation. Defibrotide was used to treat severe to very severe cases. Results: Four patients developed VOD/SOS during INO salvage therapy (at 21 and 36 days post-INO1, 77 days postINO3, and 21 days post-INO5), while three were diagnosed at 2, 5, and 10 days post-HSCT following INO-induced CR.Doppler ultrasonography revealed preserved portal vein flow (range 10.2–26.0 cm/sec) and normal hepatic artery resistive index (RI, range 0.56–0.74) in all but one patient (RI 0.83). Despite this, all patients presented with massive ascites and progressively elevated total bilirubin levels. All cases were classified as severe to very severe; six were treated with defibrotide and one underwent liver transplantation. Most patients ultimately died owing to VOD/SOS progression. Conclusion Post-INO VOD/SOS manifested as two different clinical settings and was characterized by preserved portal vein flow, which complicated diagnosis. Despite timely defibrotide administration, clinical outcomes were poor.These findings emphasize the need for vigilance and potential consideration of prophylactic strategies for prevention of INO-associated VOD/SOS.

Purpose: Inotuzumab ozogamicin (INO) has demonstrated a safe bridging role to allogeneic hematopoietic stem cell transplantation (HSCT) in patients with relapsed or refractory B-cell acute lymphoblastic leukemia (R/R B-ALL). How‑ ever, hepatic veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) is frequently observed. This study aimed to identify significant features of INO-associated VOD/SOS. Methods: We reviewed seven cases of hepatic VOD/SOS that developed either during INO salvage or after alloge‑ neic HSCT following INO-induced complete remission (CR). Diagnosis and severity grading of VOD/SOS were based on the revised criteria from the European Society for Blood and Marrow Transplantation. Defibrotide was used to treat severe to very severe cases. Results: Four patients developed VOD/SOS during INO salvage therapy (at 21 and 36 days post-INO1, 77 days postINO3, and 21 days post-INO5), while three were diagnosed at 2, 5, and 10 days post-HSCT following INO-induced CR.Doppler ultrasonography revealed preserved portal vein flow (range 10.2–26.0 cm/sec) and normal hepatic artery resistive index (RI, range 0.56–0.74) in all but one patient (RI 0.83). Despite this, all patients presented with massive ascites and progressively elevated total bilirubin levels. All cases were classified as severe to very severe; six were treated with defibrotide and one underwent liver transplantation. Most patients ultimately died owing to VOD/SOS progression. Conclusion Post-INO VOD/SOS manifested as two different clinical settings and was characterized by preserved portal vein flow, which complicated diagnosis. Despite timely defibrotide administration, clinical outcomes were poor.These findings emphasize the need for vigilance and potential consideration of prophylactic strategies for prevention of INO-associated VOD/SOS.

Background: and Purpose To determine the clinical phenotypes, relapse timing, treatment responses, and outcomes of children with relapsing myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). Methods: We collected the demographic, clinical, laboratory, and radiological data of patients aged <18 years who had been diagnosed with MOGAD at Seoul National University Children’s Hospital between January 2010 and January 2022; 100 were identified as positive for MOG antibodies, 43 of whom experienced relapse. Results: The median age at onset was 7 years (range 2–16 years). The median number of relapses was 2 (range 1–8), and patients were followed up for a median of 65 months (range 5–214 months). The first relapse was experienced before 3 months from onset by 15 patients (34.9%). The most-common initial phenotypes were acute disseminated encephalomyelitis (n=17, 39.5%) and optic neuritis (ON; n=11, 25.6%). The most-common relapse phenotypes were neuromyelitis optica spectrum disorder (n=9, 20.9%), relapsing ON (n=6, 14.0%), and multiphasic disseminated encephalomyelitis (n=6, 14.0%). Many of the patients (n=18, 41.9%) were not specifically categorized. A high proportion of these patients had non-acute disseminated encephalomyelitis encephalitis. Atypical phenotypes such as prolonged fever or hemiplegic migraine-like episodes were also noted. Mycophenolate mofetil and cyclic immunoglobulin treatment significantly reduced the annual relapse rates. Conclusions Our 43 pediatric patients with relapsing MOGAD showed a tendency toward early relapse and various relapse phenotypes. The overall prognoses of these patients were good regardless of phenotype or response to second-line immunosuppressant treatment.