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.

In recent years, next-generation sequencing (NGS)–based genetic testing has become crucial in cancer care. While its primary objective is to identify actionable genetic alterations to guide treatment decisions, its scope has broadened to encompass aiding in pathological diagnosis and exploring resistance mechanisms. With the ongoing expansion in NGS application and reliance, a compelling necessity arises for expert consensus on its application in solid cancers. To address this demand, the forthcoming recommendations not only provide pragmatic guidance for the clinical use of NGS but also systematically classify actionable genes based on specific cancer types. Additionally, these recommendations will incorporate expert perspectives on crucial biomarkers, ensuring informed decisions regarding circulating tumor DNA panel testing.

In recent years, next-generation sequencing (NGS)–based genetic testing has become crucial in cancer care. While its primary objective is to identify actionable genetic alterations to guide treatment decisions, its scope has broadened to encompass aiding in pathological diagnosis and exploring resistance mechanisms. With the ongoing expansion in NGS application and reliance, a compelling necessity arises for expert consensus on its application in solid cancers. To address this demand, the forthcoming recommendations not only provide pragmatic guidance for the clinical use of NGS but also systematically classify actionable genes based on specific cancer types. Additionally, these recommendations will incorporate expert perspectives on crucial biomarkers, ensuring informed decisions regarding circulating tumor DNA panel testing.

Purpose: Pulmonary sarcomatoid carcinoma (PSC) is recognized for its aggressiveness and poor prognosis. The role of radical radiotherapy in PSC remains uncertain due to its scarcity and limited data. In the absence of an effective systemic agent, this study aims to explore the possibility of cure and to investigate potential prognostic factors and treatment outcomes. Materials and Methods: From January 2005 to December 2021, 149 PSC patients were identified. Among 62 patients who received radiotherapy for lung lesions, 25 who underwent palliative radiotherapy and 16 who underwent surgery were excluded. Results: The median patient age was 71 years. The majority were male, and 17 patients (81.0%) were diagnosed at an advanced stage. After radical radiotherapy, distant metastasis (47.6%) was the most common site of failure, while the local recurrence rate was quite low (9.5%). Eventually, five patients (26.3%) demonstrated either a partial response or complete remission, including three complete remissions with durable responses. The median progression-free survival (PFS) and overall survival were 4.6 months and 7.9 months, respectively. Univariate and multivariate analyses revealed that a tumor size >5 cm was associated with a worse prognosis (p = 0.045), while a radiation dose >58 GyEQD2 was significantly associated with better PFS (p = 0.038). Conclusion This study demonstrates clinical outcomes after radical radiotherapy in managing PSC, suggesting tumor size and radiation dose could be a predictor of a systemic response. Given the known bad prognosis but complete remission could be achieved in certain subgroups, future research should explore the potential strategies using radical radiotherapy for this challenging patient population.

Objectives: The prognostic significance of CDC42 effector protein 2 (CDC42EP2) and its association with tumor-infiltrating immune cells (TIICs) have not been explored in liver hepatocellular carcinoma (LIHC). This study aims to assess the potential prognostic value of CDC42EP2 by conducting a comprehensive analysis of online databases pertaining to LIHC. Methods: We evaluated the potential of CDC42EP2 as a prognostic biomarker by utilizing online databases such as TIMER, GEPIA2, KM, OSlihc, HPA, and LinkedOmics. Results: In LIHC, we observed that the mRNA and protein expression of CDC42EP2 were upregulated compared to normal tissues. Upregulated CDC42EP2 expression was associated with a worse prognosis based on the clinicopathological characteristics of patients with LIHC. Furthermore, CDC42EP2 was positively associated with TIICs. In the co-expression and functional enrichment analyses of CDC42EP2, 11,416 genes showed positive associations with CDC42EP2 while 8,008 genes showed negative associations. CDC42EP2-related co-expression genes were involved in protein localization to the endoplasmic reticulum, translational initiation, and RNA catabolic processes in gene set enrichment analysis-Gene Ontology (GSEA-GO), and regulated the ribosome, spliceosome, and primary immune deficiency in the GSEA-Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway. In a survival map, 23 and 17 genes that exhibited positive associations with CDC42EP2 showed a significant hazard ratio (HR) for overall survival and disease-free survival, respectively. Conclusion Our findings demonstrated that CDC42EP2 is a novel prognostic biomarker and a potential tumor immune therapeutic target in patients with LIHC.

Background and Objectives: Papillary thyroid carcinoma (PTC) with lateral neck lymph node metastasis is known as a major risk factor for tumor recurrence after surgical treatment. The aim of this study is to identify risk factors for loco-regional recurrence in patients with PTC with lateral neck lymph node metastasis, which has a high risk of recurrence.Subjects and Method This study involved 319 patients who underwent total thyroidectomy, central lymph node (LN) and lateral LN dissection due to PTC. The patients’ demographics and pathological factors, including lymph node metastasis were retrospectively reviewed. Univariate, multivariate and C-index with variable selection analyses were performed to identify factors associated with recurrence-free survival (RFS). Results: A mean follow-up of 101 months, 35 (10.9%) patients had a loco-regional recurrence. In multivariate analysis according to loco-regional recurrence, patients with a primary tumor of more than 4 cm, multifocality, vascular invasion, and bilateral lateral cervical metastasis were associated with worse RFS. In the variable selection analysis, lateral lymph node metastasis ratio was also statistically significant. Conclusion PTC with lateral neck lymph node metastasis included tumors larger than 4 cm. Multifocality, vascular invasion, high lateral lymph node metastasis ratio and bilateral neck lymph node metastasis are predictive factors of loco-regional recurrence, and these risk factors should be carefully followed-up after surgery.

Objectives: This study aimed to test the effect of photodynamic therapy (PDT) on the inhibition and removal of biofilms containing multidrug-resistant Acinetobacter baumannii. Methods: Using multidrug-resistant A. baumannii strains, an antibiotic susceptibility test was performed using the Gram-negative identification card of the Vitek 2 system (bioMérieux Inc., France), as well as an analysis of resistance genes, the effects of treatment with a light-emitting diode (LED) array using Radachlorin (RADA-PHARMA Co., Ltd., Russia), and transmission and scanning electron microscopy to confirm the biofilm-inhibitory effect of PDT. Results: The antibiotic susceptibility test revealed multiple resistance to the antibiotics imipenem and meropenem in the carbapenem class. A class-D–type β-lactamase was found, and OXA-23 and OXA-51 were found in 100% of 15 A. baumannii strains. After PDT using Radachlorin, morphological observations revealed an abnormal structure due to the loss of the cell membrane and extensive morphological changes, including low intracellular visibility and small vacuoles attached to the cell membrane. Conclusion PDT involving a combination of LED and Radachlorin significantly eliminated the biofilm of multidrug-resistant A. baumannii. Observations made using electron microscopy showed that PDT combining LED and Radachlorin was effective. Additional studies on the effective elimination of biofilms containing multidrug-resistant bacteria are necessary, and we hope that a treatment method superior to sterilization with antibiotics will be developed in the future.

Background/Aims: The aim of this study was to investigate long-term post-discontinuation outcomes in patients with rheumatoid arthritis (RA) who had been treated with tumor necrosis factor-α inhibitors (TNF-αi) which was then discontinued. Methods: Sixty Korean patients with RA who participated in a 5-year GO-BEFORE and GO-FORWARD extension trials were included in this retrospective study. Golimumab was deliberately discontinued after the extension study (baseline). Patients were then followed by their rheumatologists. We reviewed their medical records for 2 years (max 28 months) following golimumab discontinuation. Patients were divided into a maintained benefit (MB) group and a loss-of-benefit (LB) group based on treatment pattern after golimumab discontinuation. The LB group included patients whose conventional disease-modifying antirheumatic drug(s) were stepped-up or added/switched (SC) and those who restarted biologic therapy (RB). Results: The mean age of patients at baseline was 56.5 years and 55 (91.7%) were females. At the end of follow-up, 23 (38.3%) patients remained in the MB group. In the LB group, 75.7% and 24.3% were assigned into SC and RB subgroups, respectively. Fifty percent of patients lost MB after 23.3 months. Demographics and clinical variables at baseline were comparable between MB and LB groups except for age, C-reactive protein level, and corticosteroid use. Restarting biologic therapy was associated with swollen joint count (adjusted hazard ratio [HR], 1.90; 95% confidence interval [CI], 1.01 to 3.55) and disease duration (adjusted HR, 1.12; 95% CI, 1.02 to 1.23) at baseline. Conclusions Treatment strategies after discontinuing TNF-αi are needed to better maintain disease control and quality of life of patients with RA.