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: TP53 mutations are associated with poor prognosis in myelodysplastic neoplasm (MDS) and AML. The updated 5th WHO classification and International Consensus Classification (ICC) categorize TP53-mutated MDS and AML as unique entities. We conducted a multicenter study in Korea to investigate the characteristics of TP53-mutated MDS and AML, focusing on diagnostic aspects based on updated classifications. Methods: This study included patients aged ≥ 18 yrs who were diagnosed as having MDS(N = 1,244) or AML (N = 2,115) at six institutions. The results of bone marrow examination, cytogenetic studies, and targeted next-generation sequencing, including TP53, were collected and analyzed. Results: TP53 mutations were detected in 9.3% and 9.2% of patients with MDS and AML, respectively. Missense mutation was the most common, with hotspot codons R248/ R273/G245/Y220/R175/C238 accounting for 25.4% of TP53 mutations. Ten percent of patients had multiple TP53 mutations, and 78.4% had a complex karyotype. The median variant allele frequency (VAF) of TP53 mutations was 41.5%, with a notable difference according to the presence of a complex karyotype. According to the 5th WHO classification and ICC, the multi-hit TP53 mutation criteria were met in 58.6% and 75% of MDS patients, respectively, and the primary determinants were a TP53 VAF > 50% for the 5th WHO classification and the presence of a complex karyotype for the ICC. Conclusions Collectively, we elucidated the molecular genetic characteristics of patients with TP53-mutated MDS and AML, highlighting key factors in applying TP53 mutation-related criteria in updated classifications, which will aid in establishing diagnostic strategies.

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.