Gastric cancer is one of the most common cancers in both Korea and worldwide. Since 2004, the Korean Practice Guidelines for Gastric Cancer have been regularly updated, with the 4th edition published in 2022. The 4th edition was the result of a collaborative work by an interdisciplinary team, including experts in gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology, and guideline development methodology. The current guideline is the 5th version, an updated version of the 4th edition. In this guideline, 6 key questions (KQs) were updated or proposed after a collaborative review by the working group, and 7 statements were developed, or revised, or discussed based on a systematic review using the MEDLINE, Embase, Cochrane Library, and KoreaMed database. Over the past 2 years, there have been significant changes in systemic treatment, leading to major updates and revisions focused on this area.Additionally, minor modifications have been made in other sections, incorporating recent research findings. The level of evidence and grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation system. Key factors for recommendation included the level of evidence, benefit, harm, and clinical applicability. The working group reviewed and discussed the recommendations to reach a consensus. The structure of this guideline remains similar to the 2022 version.Earlier sections cover general considerations, such as screening, diagnosis, and staging of endoscopy, pathology, radiology, and nuclear medicine. In the latter sections, statements are provided for each KQ based on clinical evidence, with flowcharts supporting these statements through meta-analysis and references. This multidisciplinary, evidence-based gastric cancer guideline aims to support clinicians in providing optimal care for gastric cancer patients.

Gastric cancer is one of the most common cancers in both Korea and worldwide. Since 2004, the Korean Practice Guidelines for Gastric Cancer have been regularly updated, with the 4th edition published in 2022. The 4th edition was the result of a collaborative work by an interdisciplinary team, including experts in gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology, and guideline development methodology. The current guideline is the 5th version, an updated version of the 4th edition. In this guideline, 6 key questions (KQs) were updated or proposed after a collaborative review by the working group, and 7 statements were developed, or revised, or discussed based on a systematic review using the MEDLINE, Embase, Cochrane Library, and KoreaMed database. Over the past 2 years, there have been significant changes in systemic treatment, leading to major updates and revisions focused on this area.Additionally, minor modifications have been made in other sections, incorporating recent research findings. The level of evidence and grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation system. Key factors for recommendation included the level of evidence, benefit, harm, and clinical applicability. The working group reviewed and discussed the recommendations to reach a consensus. The structure of this guideline remains similar to the 2022 version.Earlier sections cover general considerations, such as screening, diagnosis, and staging of endoscopy, pathology, radiology, and nuclear medicine. In the latter sections, statements are provided for each KQ based on clinical evidence, with flowcharts supporting these statements through meta-analysis and references. This multidisciplinary, evidence-based gastric cancer guideline aims to support clinicians in providing optimal care for gastric cancer patients.

Gastric cancer is one of the most common cancers in both Korea and worldwide. Since 2004, the Korean Practice Guidelines for Gastric Cancer have been regularly updated, with the 4th edition published in 2022. The 4th edition was the result of a collaborative work by an interdisciplinary team, including experts in gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology, and guideline development methodology. The current guideline is the 5th version, an updated version of the 4th edition. In this guideline, 6 key questions (KQs) were updated or proposed after a collaborative review by the working group, and 7 statements were developed, or revised, or discussed based on a systematic review using the MEDLINE, Embase, Cochrane Library, and KoreaMed database. Over the past 2 years, there have been significant changes in systemic treatment, leading to major updates and revisions focused on this area.Additionally, minor modifications have been made in other sections, incorporating recent research findings. The level of evidence and grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation system. Key factors for recommendation included the level of evidence, benefit, harm, and clinical applicability. The working group reviewed and discussed the recommendations to reach a consensus. The structure of this guideline remains similar to the 2022 version.Earlier sections cover general considerations, such as screening, diagnosis, and staging of endoscopy, pathology, radiology, and nuclear medicine. In the latter sections, statements are provided for each KQ based on clinical evidence, with flowcharts supporting these statements through meta-analysis and references. This multidisciplinary, evidence-based gastric cancer guideline aims to support clinicians in providing optimal care for gastric cancer patients.

Background: Posterior reversible encephalopathy syndrome (PRES) is a rare complication of lung transplantation with poorly understood risk factors and clinical characteristics. This study aimed to examine the occurrence, risk factors, and clinical data of patients who developed PRES following lung transplantation. Methods: A retrospective analysis was conducted on 147 patients who underwent lung transplantation between February 2013 and December 2023. The patients were diagnosed with PRES based on the clinical symptoms and radiological findings. We compared the baseline characteristics and clinical information, including primary lung diseases and immunosuppressive therapy related to lung transplantation operations, between the PRES and non-PRES groups. Results: PRES manifested in 7.5% (n=11) of the patients who underwent lung transplantation, with a median onset of 15 days after operation. Seizures were identified as the predominant clinical manifestation (81.8%, n=9) in the group diagnosed with PRES. All patients diagnosed with PRES recovered fully. Patients with PRES were significantly associated with connective tissue disease-associated interstitial lung disease (45.5% vs. 18.4%, P=0.019, odds ratio=9.808; 95% CI, 1.064–90.386; P=0.044). Nonetheless, no significant variance was observed in the type of immunotherapy, such as the use of calcineurin inhibitors, blood pressure, or acute renal failure subsequent to lung transplantation. Conclusions PRES typically manifests shortly after lung transplantation, with seizures being the predominant initial symptom. The presence of preexisting connective tissue disease as the primary lung disease represents a significant risk factor for PRES following lung transplantation.

Background: Primary cutaneous CD30+ lymphoproliferative disorders (pcCD30-LPDs) are a diseases with various clinical and prognostic characteristics. Objective: Increasing our knowledge of the clinical characteristics of pcCD30-LPDs and identifying potential prognostic variables in an Asian population. Methods: Clinicopathological features and survival data of pcCD30-LPD cases obtained from 22 hospitals in South Korea were examined. Results: A total of 413 cases of pcCD30-LPDs (lymphomatoid papulosis [LYP], n=237; primary cutaneous anaplastic large cell lymphoma [C-ALCL], n=176) were included. Ninety percent of LYP patients and roughly 50% of C-ALCL patients presented with multiple skin lesions. Both LYP and C-ALCL affected the lower limbs most frequently. Multiplicity and advanced T stage of LYP lesions were associated with a chronic course longer than 6 months. Clinical morphology with patch lesions and elevated serum lactate dehydrogenase were significantly associated with LPDs during follow-up in LYP patients. Extracutaneous involvement of C-ALCL occurred in 13.2% of patients. Lesions larger than 5 cm and increased serum lactate dehydrogenase were associated with a poor prognosis in C-ALCL. The survival of patients with C-ALCL was unaffected by the anatomical locations of skin lesions or other pathological factors. Conclusion The multiplicity or size of skin lesions was associated with a chronic course of LYP and survival among patients with C-ALCL.

Background/Aims: Although important, clinically significant liver fibrosis is often overlooked in the general population. We aimed to examine the prevalence of clinically significant liver fibrosis using noninvasive tests (NITs) in the general population. Methods: We collected data from four databases (MEDLINE, Embase, Cochrane Library, and KoreaMed) from inception to June 13, 2023. Original articles reporting the prevalence of clinically significant liver fibrosis in the general population were included. The Stata metaprop function was used to obtain the pooled prevalence of liver fibrosis with NITs in the general population. Results: We screened 6,429 articles and included 45 eligible studies that reported the prevalence of clinically significant liver fibrosis in the general population. The prevalence of advanced liver fibrosis, using the high probability cutoff of the fibrosis-4 (FIB-4) index, was 2.3% (95% confidence interval [CI], 1.2–3.7%). The prevalence of significant liver fibrosis, advanced liver fibrosis, and liver cirrhosis, assessed using vibration-controlled transient elastography (VCTE) among the general population, was 7.3% (95% CI, 5.9–8.8%), 3.5% (95% CI, 2.7–4.5), and 1.2% (95% CI, 0.8–1.8%), respectively. Region-based subgroup analysis revealed that the highest prevalence of advanced fibrosis using the high probability cutoff of the FIB-4 index was observed in the American region. Furthermore, the American region exhibited the highest prevalence of significant liver fibrosis, advanced liver fibrosis, and liver cirrhosis, using VCTE. Conclusions Previously undiagnosed clinically significant liver fibrosis is found in the general population through NITs. Future research is necessary to stratify the risk in the general population.

Background: s/Aims: Liver stiffness measurement (LSM) using vibration-controlled transient elastography (VCTE) can assess fibrotic burden in chronic liver diseases. The systematic review and meta-analysis was conducted to determine whether LSM using VCTE can predict the risk of development of hepatocellular carcinoma (HCC) in chronic hepatitis B (CHB) patients. Methods: A systematic literature search of the Ovid-Medline, EMBASE, Cochrane, and KoreaMed databases (from January 2010 to June 2023) was conducted. Of the 1,345 individual studies identified, 10 studies that used VCTE were finally registered. Hazard ratios (HRs) and the 95% confidence intervals (CIs) were considered summary estimates of treatment effect sizes of ≥11 kilopascal (kPa) standard for HCC development. Meta-analysis was performed using the restricted Maximum Likelihood random effects model. Results: Among the ten studies, data for risk ratios for HCC development could be obtained from nine studies. When analyzed for the nine studies, the HR for HCC development was high at 3.33 (95% CI, 2.45–4.54) in CHB patients with a baseline LSM of ≥11 kPa compared to patients who did not. In ten studies included, LSM of ≥11 kPa showed the sensitivity and specificity for predicting HCC development were 61% (95% CI, 50–71%) and 78% (95% CI, 66–86%), respectively, and the diagnostic accuracy was 0.74 (95% CI, 0.70–0.77). Conclusions The risk of HCC development was elevated in CHB patients with VCTE-determined LSM of ≥11 kPa. This finding suggests that VCTE-determined LSM values may aid the risk prediction of HCC development in CHB patients.

Background/Aims: The Fibrosis-4 index (FIB-4) is a noninvasive test widely used to rule out advanced liver fibrosis (AF) in patients with nonalcoholic fatty liver disease (NAFLD). However, its diagnostic accuracy in NAFLD patients with type 2 diabetes mellitus (T2DM) is controversial due to the high prevalence of AF in this population. Methods: Research focusing on the diagnostic accuracy of FIB-4 for liver fibrosis as validated by liver histology in NAFLD patients with T2DM was included, and 12 studies (n=5,624) were finally included in the meta-analysis. Sensitivity, specificity, hierarchical summary receiver operating characteristic (HSROC), positive predictive values (PPVs), and negative predictive values (NPVs) at low cutoffs (1.3–1.67) and high cutoffs (2.67–3.25) for ruling in and out AF were calculated. Results: At low cutoffs, the meta-analysis revealed a sensitivity of 0.74, specificity of 0.62, and HSROC of 0.75. At high cutoffs, the analysis showed a sensitivity of 0.33, specificity of 0.92, and HSROC of 0.85, suggesting FIB-4 as useful for identifying or excluding AF. In subgroup analyses, high mean age and F3 prevalence were associated with lower sensitivity. The calculated NPV and PPV were 0.82 and 0.49 at low cutoffs, whereas the NPV was 0.28 and the PPV was 0.70 at high cutoffs. There were insufficient estimated NPVs <0.90 at a hypothesized prevalence of AF >30% at an FIB-4 cutoff range of 1.3–1.67. Conclusions Collectively, FIB-4 has moderate diagnostic accuracy for identifying or excluding AF in NAFLD patients with T2DM, but more evidence must be accumulated due to the limited number of currently reported studies and their heterogeneity.

Background: s/Aims: Despite advances in antiviral therapy for hepatitis C virus (HCV) infection, hepatocellular carcinoma (HCC) still develops even after sustained viral response (SVR) in patients with advanced liver fibrosis or cirrhosis. This meta-analysis investigated the predictive performance of vibration-controlled transient elastography (VCTE) and fibrosis 4-index (FIB-4) for the development of HCC after SVR. Methods: We searched PubMed, MEDLINE, EMBASE, and the Cochrane Library for studies examining the predictive performance of these tests in adult patients with HCV. Two authors independently screened the studies’ methodological quality and extracted data. Pooled estimates of sensitivity, specificity, and area under the curve (AUC) were calculated for HCC development using random-effects bivariate logit normal and linear-mixed effect models. Results: We included 27 studies (169,911 patients). Meta-analysis of HCC after SVR was possible in nine VCTE and 15 FIB-4 studies. Regarding the prediction of HCC development after SVR, the pooled AUCs of pre-treatment VCTE >9.2–13 kPa and FIB-4 >3.25 were 0.79 and 0.73, respectively. VCTE >8.4–11 kPa and FIB-4 >3.25 measured after SVR maintained good predictive performance, albeit slightly reduced (pooled AUCs: 0.77 and 0.70, respectively). The identified optimal cut-off value for HCC development after SVR was 12.6 kPa for pre-treatment VCTE. That of VCTE measured after the SVR was 11.2 kPa. Conclusions VCTE and FIB-4 showed acceptable predictive performance for HCC development in patients with HCV who achieved SVR, underscoring their utility in clinical practice for guiding surveillance strategies. Future studies are needed to validate these findings prospectively and validate their clinical impact.