Purpose: To develop the 2025 update to the Korean colorectal cancer (CRC) screening guidelines by systematically evaluating recent evidence, integrating domestic data, and addressing changes since the 2015 guideline revision, thereby providing an evidence-based standard for clinicians and policymakers. Methods: A multidisciplinary committee developed the guidelines using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology. The process included formulation of three key questions addressing screening efficacy, diagnostic accuracy, and optimal screening age and interval. A systematic review of international guidelines and primary literature was conducted, yielding 327 eligible studies. In addition, a utility-based analysis using a Markov model was performed to determine optimal screening ages and intervals. Results: The evidence synthesis identified high-certainty evidence supporting the use of the fecal immunochemical test (FIT) for reducing CRC mortality and moderate-certainty evidence for colonoscopy. Evidence for computed tomographic colonography (CTC) and stool DNA testing was rated as very low certainty. Based on the evidence review and cost-utility analysis, the committee conditionally recommends CRC screening for asymptomatic, average-risk adults aged 45–74 years using either colonoscopy every 10 years or FIT every 1–2 years. CTC and stool DNA testing were not recommended owing to insufficient evidence. Conclusion The 2025 Korean Guidelines for Colorectal Cancer Screening present updated, evidence-based recommendations tailored to the domestic healthcare context. By conditionally endorsing both colonoscopy and FIT for individuals aged 45–74 years, these guidelines aim to improve population-level screening effectiveness and reduce the burden of CRC in South Korea.

Objectives: This study aims to investigate the challenges faced by individuals with schizophrenia in adhering to COVID-19 prevention guidelines and the difficulties they experienced due to social distancing measures. Methods: The study focused on 286 registered members with schizophrenia who were utilizing mental health welfare center services in the Busan area. The general control group consisted of individuals aged 19 and older in Busan. A survey was used to examine changes in daily life due to COVID-19 and perceptions of preventive measures. The survey also investigated the difficulties in daily life and the services needed by individuals with schizophrenia after the onset of COVID-19.To compare the two groups, independent sample t-tests were used for continuous variables, and chi-square tests were conducted for categorical variables. Results: Compared to the general population, individuals with schizophrenia reported lower levels of anxiety about contracting COVID-19 and experiencing fatal outcomes. They also indicated that they were less likely to engage in new activities or experience conflicts with those around them. Additionally, they rated the necessity of COVID-19 preventive guidelines lower and reported experiencing less stress from adhering to these guidelines. However, individuals with schizophrenia expressed significant discomfort due to the reduction in face-to-face counseling as a result of the suspension of mental health welfare center services. They also reported difficulties with attending outpatient appointments and maintaining regular meals, among other challenges. Conclusions In this study, it was observed that individuals with schizophrenia tended to underestimate the risk and severity of COVID-19 infection and found it challenging to recognize the necessity of preventive measures. Additionally, they appeared to experience greater difficulties in managing their daily lives independently.

Ketamine is commonly used in the emergency department for procedural sedation. It is the most commonly chosen sedative drug in children because of its rapid onset, short half-life, little respiratory depression, and can be administered intravenously and intramuscularly. Common side effects include hallucination, visual disturbance, dizziness, nausea, and vomiting. Recently, it has also been used as an anticonvulsant for refractory status epilepticus. The authors encountered a case of generalized tonic-clonic seizure in a four-year-old boy after an intramuscular injection of ketamine for procedural sedation. This case is reported to share the author’s experience with medical professionals who use ketamine and raise awareness.

Background: In February 2024, a sudden government policy to drastically increase medical school admissions triggered the mass resignations of medical trainees across South Korea, severely disrupting hospital operations. This study aimed to evaluate the impact of the resulting healthcare workforce disruptions on short-term clinical outcomes and the timing of colorectal cancer surgeries. Methods: This retrospective comparative study analyzed patients with colorectal cancer treated at two national university hospitals in Daegu and Gwangju, South Korea. Patients who first visited the colorectal surgery department between March and August of 2023 and 2024 were included. Data from 2020 to 2022 were used for extended comparisons. The primary outcome was the interval from initial outpatient visit to surgery. Secondary outcomes included treatment modality distribution, tumor staging, and postoperative complications. Results: A total of 895 patients in 2023 and 853 in 2024 were included. In 2024, only 39.5% of patients (337/853) underwent upfront surgery compared to 63.5% (569/895) in 2023. The median time to surgery increased from 30 days (interquartile range [IQR], 22–44 days) to 52 days (IQR, 30–72 days) (p=0.001). Clinical T3–4 tumors increased from 49.9% to 59.3% (p=0.018), lymph node-positive cases increased from 25.9% to 51.3% (p=0.001), and postoperative complication rates increased from 12.0% to 28.2% (p=0.001). Conclusion The abrupt healthcare workforce crisis in early 2024 significantly delayed colorectal cancer surgeries and was associated with worse short-term oncologic outcomes. These findings highlight the critical importance of maintaining a stable healthcare workforce to protect access to timely cancer care.

Background: Human muscle satellite (stem) cells (MuSCs) are essential for investigating muscle physiology, regeneration, and disease mechanisms. Primary cultures derived directly from human tissues offer a more physiologically relevant model than immortalized cell lines. However, the isolation and characterization of MuSCs from human upper limb tissues are limited. Therefore, this study aimed to establish and characterize a primary culture system for MuSCs obtained from human upper limb muscle tissue. Methods: Human muscle tissues were obtained from upper limb surgical specimens. Muscle samples were mechanically and enzymatically dissociated to isolate muscle-derived cells, which were cultured under standard growth conditions. Cell morphology and proliferation were monitored during the culture period. Myogenic characteristics were assessed by examining the expression of muscle-specific markers including myogenic regulatory factors and structural proteins. Additionally, myogenic differentiation capacity was evaluated by inducing differentiation and analyzing the formation of multinucleated myotubes. Results: Primary MuSCs were isolated from human upper limb tissues and expanded in vitro. The cultured cells exhibited a typical spindle-shaped morphology and demonstrated significant proliferative capacity. Characterization confirmed the expression of myogenic markers, indicating the presence of muscle-derived precursor cells. Following induction of differentiation, the cells formed multinucleated myotube-like structures and expressed muscle proteins associated with differentiation, highlighting their potential for myogenic differentiation. Conclusion This study established a reliable protocol for isolating and culturing MuSCs from human upper limb tissues. Cultured cells displayed typical myogenic characteristics and differentiation capacity, indicating that this model could be a valuable platform for studying human muscle biology and potential therapeutic applications.

Varicella-zoster virus (VZV) establishes lifelong latency following primary infection and can reactivate later in life to cause herpes zoster (HZ) and its debilitating complication postherpetic neuralgia (PHN). The implementation of varicella vaccinations has profoundly altered the epidemiological landscape of VZV. This narrative review examines the current literature to evaluate the impact of these vaccination programs on the incidence of HZ and PHN. Early mathematical models based on the “exogenous boosting” hypothesis predicted a substantial surge in adult HZ due to reduced exposure to circulating wild-type virus. However, long-term epidemiological data demonstrate that the incidence of adult HZ was already increasing prior to the introduction of vaccination programs and did not accelerate post-implementation, suggesting other primary drivers, such as an aging population. This review highlights the significant decline in HZ incidence among vaccinated pediatric populations, as the attenuated vOka vaccine strain is substantially less prone to reactivation than the wild-type virus. Furthermore, HZ that does occur in vaccinated individuals tends to be milder, resulting in a reduced risk of progression to PHN. To address the persistent risk in older adults, a recombinant zoster vaccine is recommended as a highly effective secondary prevention strategy. Despite challenges, such as breakthrough infections and the need for long-term monitoring of vaccine-induced immunity, varicella vaccination remains a cornerstone of public health, offering broad protection across different ages. Further research is needed to fully understand the long-term impact of varicella vaccinations on the incidence of HZ and PHN and to identify additional risk factors for these conditions.

Background: Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of advanced malignant melanoma. This study examined the real-world efficacy of dacarbazine (dimethyl triazeno imidazole carboxamide, DTIC) in patients who had previously received pembrolizumab, based on the hypothesis that prior ICI treatment enhances the therapeutic response to subsequent chemotherapy. Methods: This retrospective study included 71 patients with histologically confirmed malignant melanoma treated at Kyungpook National University Chilgok Hospital (Daegu, Korea) between 2011 and 2023. The patients received DTIC for unresectable stage IIIC, IIID, or IV melanoma (American Joint Committee on Cancer, 8th edition). Results: Among the 71 patients, the median patient age was 64 years (range, 25–89 years). When categorized by melanoma subtype, 18 patients (25.4%) had acral melanoma, 40 (56.3%) had cutaneous melanoma, and 13 (18.3%) had mucosal melanoma. Sixteen of the DTIC-treated patients had not received pembrolizumab previously (DTIC-only group), while 55 had (pem-DTIC group). The median progression-free survival was 2.3 months in the DTIC-only group and 3.9 months in the pem-DTIC group (hazard ratio [HR], 0.246; 95% confidence interval [CI], 0.106–0.576; p=0.001). The median overall survival was 6.8 months in the DTIC-only group and 19.0 months in the pem-DTIC group (HR, 0.198; 95% CI, 0.068–0.574; p=0.003). The duration of response (DoR) was 4.64 months in the DTIC group and 8.11 months in the pem-DTIC group. Conclusion This study demonstrated that the DoR to DTIC was prolonged following ICI therapy (4.64 months vs. 8.11 months). This indicates that prior ICI treatment may enhance tumor sensitivity to chemotherapy, making DTIC a viable option for treating refractory, relapsed, or progressive melanoma.

Background: Early oral switch (EOS) has been proposed as an alternative to prolonged intravenous (IV) therapy for Enterobacterales bacteremia; however, its safety and effectiveness have not been clearly established. This systematic review and meta-analysis evaluated whether EOS reduces treatment failure in uncomplicated Enterobacterales bacteremia and examined how the timing of switching affects outcomes. Methods: We conducted a systematic review and random-effects meta-analysis of randomized controlled trials and observational studies that compared EOS with continued IV therapy in adults with uncomplicated Enterobacterales bacteremia. Pooled risk ratios (RRs) with 95% confidence intervals (CIs) were calculated using random-effects models. The primary outcome was treatment failure by ≤90 days. Prespecified analyses evaluated the timing of the switch. Results: Across 10 studies that met the inclusion criteria, EOS was associated with lower treatment failure than continued IV therapy (RR, 0.72; 95% CI, 0.58–0.89; I²=26%). Switching within 4 days reduced the failure (RR, 0.58; 95% CI, 0.44–0.76; I²=0%), whereas switching after 4 days showed no clear advantage (RR, 0.87; 95% CI, 0.71–1.06; I²=0%). No evidence of small study effects was observed. Conclusion EOS was associated with a lower risk of treatment failure than prolonged IV therapy, with the greatest benefit observed when the switch occurred within 4 days. These findings should be interpreted with clinical caution given that most of the evidence is observational.

Background: Quadratus lumborum (QL) block is used for multimodal analgesia following abdominal surgery. We introduced an ultrasound-guided QL block to treat postoperative pain for ileostomy closure. This study aimed to investigate the analgesic efficacy of the QL block compared to placebo after ileostomy closure. Methods: Fifty-seven patients undergoing elective ileostomy closure were randomized (1:1) to the placebo or QL block group in this double-blind randomized controlled trial. After general anesthesia, a unilateral QL block was performed under ultrasound guidance. Opioid consumption and numeric rating scale (NRS, 0–10) pain scores were recorded at 2, 6, 12, 24, 48, and 72 hours postoperatively. The primary outcome was the NRS pain score at rest at 6 hours. Secondary outcomes included pain scores, rescue analgesics over 72 hours, Quality of Recovery-15 scores in 24 hours, complications, and length of hospital stay. Results: Baseline characteristics were similar among the 54 patients (27 per group) who completed the study, excluding three who dropped out. The QL block did not reduce NRS pain scores at rest at 6 hours (median [interquartile range], 5 [4–6] vs. 5 [3–6]; p=0.78). Over the 72-hour postoperative period, pain scores at rest remained comparable between the groups, while the QL group showed slightly lower movement-induced pain at certain time points. The QL group required fewer analgesics and antiemetics at certain intervals, but the total opioid use, length of hospital stay, and quality of recovery were not significantly different. Conclusion The QL block showed no meaningful advantage in postoperative analgesia compared to placebo for ileostomy closures.