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.

Background: Since the emergence of hypervirulent strains of Clostridioides difficile, the incidence of C. difficile infections (CDI) has increased significantly. Methods: To assess the incidence of CDI in Korea, we conducted a prospective multicentre observational study from October 2020 to October 2021. Additionally, we calculated the incidence of CDI from mass data obtained from the Health Insurance Review and Assessment Service (HIRA) from 2008 to 2020. Results: In the prospective study with active surveillance, 30,212 patients had diarrhoea and 907 patients were diagnosed with CDI over 1,288,571 patient-days and 193,264 admissions in 18 participating hospitals during 3 months of study period; the CDI per 10,000 patientdays was 7.04 and the CDI per 1,000 admission was 4.69. The incidence of CDI was higher in general hospitals than in tertiary hospitals: 6.38 per 10,000 patient-days (range: 3.25–12.05) and 4.18 per 1,000 admissions (range: 1.92–8.59) in 11 tertiary hospitals, vs. 9.45 per 10,000 patient-days (range: 5.68–13.90) and 6.73 per 1,000 admissions (range: 3.18–15.85) in seven general hospitals. With regard to HIRA data, the incidence of CDI in all hospitals has been increasing over the 13-year-period: from 0.3 to 1.8 per 10,000 patient-days, 0.3 to 1.6 per 1,000 admissions, and 6.9 to 56.9 per 100,000 population, respectively. Conclusion The incidence of CDI in Korea has been gradually increasing, and its recent value is as high as that in the United State and Europe. CDI is underestimated, particularly in general hospitals in Korea.

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.

Background: The objective of this study was to evaluate the efficacy and safety of totally thoracoscopic ablation (TTA) in patients with recurrent atrial fibrillation (AF) after radiofrequency catheter ablation (RFCA). Methods: From February 2012 to May 2020, 460 patients who underwent TTA were classified into two groups: CA (presence of RFCA history, n = 74) and nCA groups (absence of RFCA history, n = 386). Inverse probability of treatment weighting (IPTW) analyses were used to adjust for confounders. The primary endpoint was freedom from the composite of AF, typical atrial flutter, atypical atrial flutter and any atrial tachyarrhythmia, lasting more than 30 seconds during the follow-up. All patients were followed up at 3, 6, and 12 months via electrocardiogram and 24-hour Holter monitoring. Results: Bilateral pulmonary vein isolation (PVI) was conducted in all patients and the conduction block tests were confirmed. In the CA group, difficult PVI occasionally occurred due to structural changes, such as pericardial adhesion and fibrosis of the pulmonary venous structure, caused by a previous catheter ablation. Early complications such as stroke and pacemaker insertion were not different between the two groups. The normal sinus rhythm was maintained in 70.1% (317/460) patients after a median follow-up period of 38.1 months.The IPTW-weighted Kaplan-Meier curves revealed that freedom from AF events at 5 years was 68.4% (95% confidence interval, 62.8–74.5) in the nCA group and 31.2% (95% confidence interval, 16.9–57.5) in the CA group (P < 0.001). In IPTW-weighted Cox regression, preoperative left atrial diameter, persistent or long-standing AF, the presence of congestive heart failure and catheter ablation history were associated with AF events. Conclusion Patients in the CA group showed a higher recurrence rate of AF than those in the nCA group, while TTA was safely performed in both the groups.

Background: The importance of molecular pathology tests has increased during the last decade, and there is a great need for efficient training of molecular pathology for pathology trainees and as continued medical education. Methods: The Molecular Pathology Study Group of the Korean Society of Pathologists appointed a task force composed of experienced molecular pathologists to develop a refined educational curriculum of molecular pathology. A 3-day online educational session was held based on the newly established structure of learning objectives; the audience were asked to score their understanding of 22 selected learning objectives before and after the session to assess the effect of structured education. Results: The structured objectives and goals of molecular pathology was established and posted as a web-based interface which can serve as a knowledge bank of molecular pathology. A total of 201 pathologists participated in the educational session. For all 22 learning objectives, the scores of self-reported understanding increased after educational session by 9.9 points on average (range, 6.6 to 17.0). The most effectively improved items were objectives from next-generation sequencing (NGS) section: ‘NGS library preparation and quality control’ (score increased from 51.8 to 68.8), ‘NGS interpretation of variants and reference database’ (score increased from 54.1 to 68.0), and ‘whole genome, whole exome, and targeted gene sequencing’ (score increased from 58.2 to 71.2). Qualitative responses regarding the adequacy of refined educational curriculum were collected, where favorable comments dominated. Conclusions Approach toward the education of molecular pathology was refined, which would greatly benefit the future trainees.

Background: Although almost all interventional pulmonologists agree that rigid bronchoscopy is irreplaceable in the field of interventional pulmonology, less is known about the types of diseases that the procedure is used for and what difficulties the operators face during the procedure. The purpose of this study is to evaluate what diseases rigid bronchoscopy is used for, whether it is widely used, and what challenges the operators face in Korea. Methods: We enrolled 14 hospitals in this retrospective cohort of patients who underwent rigid bronchoscopy between 2003 and 2020. An online survey was conducted with 14 operators to investigate the difficulties associated with the procedure. Results: While the number of new patients at Samsung Medical Center (SMC) increased from 189 in 2003–2005 to 468 in 2018–2020, that of other institutions increased from 0 to 238.The proportion of SMC patients in the total started at 100% and steadily decreased to 59.2%.The proportion of malignancy as the indication for the procedure steadily increased from 29.1% to 43.0%, whereas post-tuberculous stenosis (25.4% to 12.9%) and post-intubation stenosis (19.0% to 10.9%) steadily decreased (all P for trends < 0.001). In the online survey, half of the respondents stated that over the past year they performed less than one procedure per month. The fewer the procedures performed within the last year, the more likely collaboration with other departments was viewed as a recent obstacle (Spearman correlation coefficient, r s = −0.740, P = 0.003) and recent administrative difficulties were encountered (r s = −0.616, P = 0.019). Conclusion This study demonstrated that the number of patients undergoing rigid bronchoscopy has been increasing, especially among cancer patients. For this procedure to be used more widely, it will be important for beginners to systematically learn about the procedure itself as well as to achieve multidisciplinary consultation.

Background: In patients with non-paroxysmal AF (atrial fibrillation), various ablation strategies have been attempted to target non-pulmonary vein (PV) foci or to achieve substrate modification beyond pulmonary vein isolation. The efficacy of empirical ablation of the SVC, one of the most common non-PV foci, is unclear. The aim of this study was to investigate the efficacy and safety of additional superior vena cava (SVC) isolation in patients with non-parox‑ ysmal AF undergoing thoracoscopic surgical ablation. Methods: /results A total of 191 patients with persistent or long-standing persistent AF was enrolled. All patients underwent total thoracoscopic surgical ablation for AF, and half of them also received empirical SVC isolation. We compared the atrial tachyarrhythmia (ATa)-free survival rate and procedure-related complications in the two groups of patients. The 3-year ATa-free survival rate was 53% in the SVC isolation group and 52% in the no-SVC isolation group (p = 0.644). There were no differences between the two groups with respect to AF type or LA size. Procedure-related complications occurred in 12 patients (6%). Pacemakers were implanted only in three patients from the SVC isolation group. The only factor influencing recurrence of ATa was LA diameter. Conclusions Empirical SVC isolation during thoracoscopic ablation for persistent AF did not improve patient outcomes.

Purpose: Patients with diabetes are known to have poor clinical outcomes due to the high incidence of complications after ankle joint fracture surgery. This study reports the clinical and functional outcomes based on glycemic control status among patients with ankle joint fractures who underwent surgical treatment. Materials and Methods: Among patients who underwent surgical treatment due to ankle joint fractures from January 2015 to October 2019, 253 patients with a minimum follow-up of 12 months were identified. We divided them into 3 groups: 195 patients with no diabetes (Group A), 26 patients with well-controlled diabetes (Group B), and 32 patients with uncontrolled diabetes (Group C). In addition, patients with lateral, medial malleolar, bimalleolar, and trimalleolar fractures were identified using radi-ography. The functional outcome measures used for evaluation were the Revised Foot Function Index (FFI), Short Musculoskeletal Function Assessment (SMFA), and the Foot and Ankle Outcome Score (FAOS). Results: Bone union at 3 months after surgery was high in Group A, showing significant differences compared to the other groups. There was a significant difference between the groups in the incidence of arthropathy and one or more complications. However, the FFI, SMFA, and FAOS did not show significant differences between the groups. Conclusion The incidence of complications was high in patients with uncontrolled diabetes compared to the patients with well-controlled diabetes and those with no diabetes. However, functional outcomes showed no significant difference.

Purpose: Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with a poor prognosis and a lack of targeted therapy. Overexpression of FRAT1 is thought to be associated with this aggressive subtype of cancer. Here, we performed a comprehensive analysis and assessed the association between overexpression of FRAT1 and TNBC. Methods: First, using different web-based bioinformatics platforms (TIMER 2.0, UALCAN, and GEPIA 2), the expression of FRAT1 was assessed. Then, the expression of the FRAT1 protein and hormone receptors and HER2 status were assessed by immunohistochemical analysis. For samples of tumors with equivocal immunoreactivity, we performed silver in situ hybridization of the HER2 gene to determine an accurate HER2 status. Next, we used the R package and bc-GenExMiner 4.8 to analyze the relationship between FRAT1 expression and clinicopathological parameters in breast cancer patients.Finally, we determined the relationship between FRAT1 overexpression and prognosis in patients. Results: The expression of FRAT1 in breast cancer tissues is significantly higher than in normal tissue. FRAT1 expression was significantly related to worse overall survival (P < 0.05) and was correlated with these clinicopathological features:T stage, N stage, age, high histologic grade, estrogen receptor status, progesterone receptor status, Her-2 status, TNBC status, basal-like status, CK5/6 status, and Ki67 status. Conclusion FRAT1 was overexpressed in breast cancer compared to normal tissue, and it may be involved in the progression of breast cancer malignancy. This study provides suggestive evidence of the prognostic role of FRAT1 in breast cancer and the therapeutic target for TNBC.