Background: s/Aims: In hepatocellular carcinoma (HCC), which exhibits high mortality and recurrence rates globally, the traits of cancer stem cells (CSCs) that significantly influence recurrence and metastasis are not well understood. CSCs are self-renewing cell types identified in most liquid and solid cancers, contributing to tumor initiation, growth, resistance, recurrence, and metastasis following chemo-radiotherapy or trans-arterial chemoembolization therapy. Methods: CSCs are classified based on the expression of cell surface markers such as CD133, which varies depending on the tumor type. Proteomic analysis of liver cancer cell lines with cancer stem cell potential and HCC cancer cell lines lacking stem cell propensity was conducted to compare and analyze specific expression patterns. Results: Proteomic profiling and enrichment analysis revealed higher expression of the calcium-binding protein S100 family in CD133+ Huh7 cells than in CD133- or wild-type cells. Furthermore, elevated expression of S100 family members was confirmed in an actual CD133+ liver cancer cell line via protein-protein network analysis and quantitative polymerase chain reaction (qPCR). Conclusion The S100 family members are not only new markers of cancer stem cells but will also assist in identifying new treatment strategies for CSC metastasis and tumor advancement.

Background/Aims: The Korean guidelines for Helicobacter pylori treatment were revised in 2020, however, the extent of adherence to these guidelines in clinical practice remains unclear. Herein, we initiated a prospective, nationwide, multicenter registry study in 2021 to evaluate the current management of H.pylori infection in Korea. Methods: This interim report describes the adherence to the revised guidelines and their impact on firstline eradication rates. Data on patient demographics, diagnoses, treatments, and eradication outcomes were collected using a web-based electronic case report form. Results: A total of 7,261 patients from 66 hospitals who received first-line treatment were analyzed.The modified intention-to-treat eradication rate for first-line treatment was 81.0%, with 80.4% of the prescriptions adhering to the revised guidelines. The most commonly prescribed regimen was the 14-day clarithromycin-based triple therapy (CTT; 42.0%), followed by tailored therapy (TT; 21.2%), 7-day CTT (14.1%), and 10-day concomitant therapy (CT; 10.1%). Time-trend analysis demonstrated significant increases in guideline adherence and the use of 10-day CT and TT, along with a decrease in the use of 7-day CTT (all p<0.001). Multivariate logistic regression analysis revealed that guideline adherence was significantly associated with first-line eradication success (odds ratio, 2.03; 95% confidence interval, 1.61 to 2.56; p<0.001). Conclusions The revised guidelines for the treatment of H. pylori infection have been increasingly adopted in routine clinical practice in Korea, which may have contributed to improved first-line eradication rates. Notably, the 14-day CTT, 10-day CT, and TT regimens are emerging as the preferred first-line treatment options among Korean physicians.

Purpose: Recent development in perioperative treatment of resectable non–small cell lung cancer (NSCLC) have changed the landscape of early lung cancer management. The ADAURA trial has demonstrated the efficacy of adjuvant osimertinib treatment in resectable NSCLC patients; however, studies are required to show which subgroup of patients are at a high risk of relapse and require adjuvant epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor treatment. This study evaluated risk factors for postoperative relapse among patients who underwent complete resection. Materials and Methods: Data were obtained from the Korean Association for Lung Cancer Registry (KALC-R), a database created using a retrospective sampling survey by the Korean Central Cancer Registry (KCCR) and the Lung Cancer Registration Committee. Results: A total of 3,176 patients who underwent curative resection was evaluated. The mean observation time was approximately 35.4 months. Among stage I to IIIA NSCLC patients, the EGFR-mutant subgroup included 867 patients, and 75.2%, 11.2%, and 11.8% were classified as stage I, stage II, and stage III, respectively. Within the EGFR-mutant subgroup, 44 (5.1%) and 121 (14.0%) patients showed early and late recurrence, respectively. Multivariate analysis on association with postoperative relapse among the EGFR-mutant subgroup showed that age, pathologic N and TNM stages, pleural invasion status, and surgery type were independent significant factors. Conclusion Among the population that underwent complete resection for early NSCLC with EGFR mutation, patients with advanced stage, pleural invasion, or limited resection are more likely to show postoperative relapse.

Purpose: The Korean Cancer Study Group (KCSG) is a nationwide cancer clinical trial group dedicated to advancing investigator-initiated trials (IITs) by conducting and supporting clinical trials. This study aims to review IITs conducted by KCSG and quantitatively evaluate the survival and financial benefits of IITs for patients. Materials and Methods: We reviewed IITs conducted by KCSG from 1998 to 2023, analyzing progression-free survival (PFS) and overall survival (OS) gains for participants. PFS and OS benefits were calculated as the difference in median survival times between the intervention and control groups, multiplied by the number of patients in the intervention group. Financial benefits were assessed based on the cost of investigational products provided. Results: From 1998 to 2023, KCSG conducted 310 IITs, with 133 completed and published. Of these, 21 were included in the survival analysis. The analysis revealed that 1,951 patients in the intervention groups gained a total of 2,558.4 months (213.2 years) of PFS and 2,501.6 months (208.5 years) of OS, with median gains of 1.31 months in PFS and 1.58 months in OS per patient. When analyzing only statistically significant results, PFS and OS gain per patients was 1.69 months and 3.02 months, respectively. Investigational drug cost analysis from six available IITs indicated that investigational products provided to 252 patients were valued at 10,400,077,294 won (approximately 8,046,481 US dollars), averaging about 41,270,148 won (approximately 31,930 US dollars) per patient. Conclusion Our findings, based on analysis of published research, suggest that IITs conducted by KCSG led to survival benefits for participants and, in some studies, may have provided financial benefits by providing investment drugs.

Background: s/Aims: In hepatocellular carcinoma (HCC), which exhibits high mortality and recurrence rates globally, the traits of cancer stem cells (CSCs) that significantly influence recurrence and metastasis are not well understood. CSCs are self-renewing cell types identified in most liquid and solid cancers, contributing to tumor initiation, growth, resistance, recurrence, and metastasis following chemo-radiotherapy or trans-arterial chemoembolization therapy. Methods: CSCs are classified based on the expression of cell surface markers such as CD133, which varies depending on the tumor type. Proteomic analysis of liver cancer cell lines with cancer stem cell potential and HCC cancer cell lines lacking stem cell propensity was conducted to compare and analyze specific expression patterns. Results: Proteomic profiling and enrichment analysis revealed higher expression of the calcium-binding protein S100 family in CD133+ Huh7 cells than in CD133- or wild-type cells. Furthermore, elevated expression of S100 family members was confirmed in an actual CD133+ liver cancer cell line via protein-protein network analysis and quantitative polymerase chain reaction (qPCR). Conclusion The S100 family members are not only new markers of cancer stem cells but will also assist in identifying new treatment strategies for CSC metastasis and tumor advancement.

Radiofrequency ablation (RFA) is a minimally invasive treatment modality used as an alternative to surgery in patients with benign thyroid nodules, recurrent thyroid cancers (RTCs), and primary thyroid microcarcinomas. The Korean Society of Thyroid Radiology (KSThR) initially developed recommendations for the optimal use of RFA for thyroid tumors in 2009 and revised them in 2012 and 2017. As new meaningful evidence has accumulated since 2017 and in response to a growing global interest in the use of RFA for treating malignant thyroid lesions, the task force committee members of the KSThR decided to update the guidelines on the use of RFA for the management of RTCs based on a comprehensive analysis of current literature and expert consensus.

Hysteroscopy is particularly valuable for the diagnosis of uterine cavity abnormalities through direct visualization. The development of office hysteroscopy has expanded the range of diagnostic and surgical procedures available. These detailed guidelines include patient counseling and the selection and setting of office hysteroscopy, including room, equipment, and medical staff. Analgesia or local anesthesia is often required in selective office hysteroscopy cases. Cervical dilation and preparation using medical or mechanical methods are required for most diagnostic hysteroscopic procedures. Methods for optimizing visualization and choosing suitable distension media are important for a successful office hysteroscopy. It is crucial to adhere to guidelines to prevent complications, such as vasovagal syncope, cervical trauma, uterine perforation, fluid overload, and embolism. Vaginoscopy can be a good alternative option for alleviating pain, especially in cases where the insertion of a vaginal speculum is expected to be challenging.

Background: s/Aims: In hepatocellular carcinoma (HCC), which exhibits high mortality and recurrence rates globally, the traits of cancer stem cells (CSCs) that significantly influence recurrence and metastasis are not well understood. CSCs are self-renewing cell types identified in most liquid and solid cancers, contributing to tumor initiation, growth, resistance, recurrence, and metastasis following chemo-radiotherapy or trans-arterial chemoembolization therapy. Methods: CSCs are classified based on the expression of cell surface markers such as CD133, which varies depending on the tumor type. Proteomic analysis of liver cancer cell lines with cancer stem cell potential and HCC cancer cell lines lacking stem cell propensity was conducted to compare and analyze specific expression patterns. Results: Proteomic profiling and enrichment analysis revealed higher expression of the calcium-binding protein S100 family in CD133+ Huh7 cells than in CD133- or wild-type cells. Furthermore, elevated expression of S100 family members was confirmed in an actual CD133+ liver cancer cell line via protein-protein network analysis and quantitative polymerase chain reaction (qPCR). Conclusion The S100 family members are not only new markers of cancer stem cells but will also assist in identifying new treatment strategies for CSC metastasis and tumor advancement.