Transforaminal endoscopic lumbar foraminotomy (TELF) is widely performed as a full-endoscopic surgical procedure for the treatment of lumbar foraminal stenosis. The technique involves the use of a small-caliber endoscopic system introduced through Kambin triangle to accomplish the primary surgical steps. However, anatomical barriers are frequently encountered in the lower lumbar segments, particularly at L4–5 and L5–S1, which may limit the feasibility of the transforaminal approach. Although various advanced transforaminal techniques have been developed to overcome these anatomical barriers, these techniques often make the procedure more technically demanding and may prolong operative time. In this video presentation, we report 2 cases in which a full-endoscopic paraspinal lumbar foraminotomy was performed to achieve adequate decompression of the exiting nerve root (ENR) without being constrained by these anatomical limitations. We also outline the procedural details and technical characteristics of this approach. Both patients presented with lumbar foraminal stenosis at the L5–S1 level, where anatomical barriers such as a high iliac crest, large transverse process, and sacral ala were present. A full-endoscopic paraspinal foraminotomy was performed at this level using a large-caliber endoscopic system, allowing sufficient decompression of the ENR and resulting in marked relief of radicular leg pain. We report a surgical procedure for full-endoscopic paraspinal lumbar foraminotomy using a large-caliber endoscopic system that permits the use of instruments of various sizes and configurations. When applied in appropriate clinical scenarios, this technique may facilitate more convenient and expedited decompression of the ENR.

Purpose: Colorectal cancer (CRC) remains a leading cause of cancer-related mortality, necessitating the identification of novel therapeutic targets. The E3 ubiquitin ligase WW domain-containing E3 ubiquitin protein ligase 2 (WWP2) has been implicated in various cancers, yet its specific role and underlying molecular mechanisms in CRC are poorly understood. This study aimed to investigate the functional role of WWP2 in CRC progression and to elucidate its regulatory mechanisms. Methods: WWP2 expression was evaluated in CRC patient tissues and cell lines using immunohistochemistry, quantitative real-time polymerase chain reaction, and western blotting. The biological functions of WWP2 were assessed using in vitro assays for cell proliferation, migration, and invasion following adenovirus-mediated overexpression. The molecular mechanism was investigated by analyzing the protein expression levels of p53 and its downstream target, p21, via western blot. An in vivo xenograft mouse model was used to confirm the oncogenic role of WWP2. Results: WWP2 expression was significantly upregulated in CRC tissues. Overexpression of WWP2 promoted CRC cell proliferation, migration, and invasion. Mechanistically, increased WWP2 expression led to a marked reduction in the protein levels of the tumor suppressor p53. Consequently, the expression of the p53 downstream target, the cell cycle inhibitor p21, was also suppressed. In the xenograft model, WWP2 overexpression significantly enhanced tumor growth. Conclusion Our findings demonstrate that WWP2 functions as an oncogene in CRC. It promotes cancer progression by destabilizing the tumor suppressor p53 and downregulating p21. This study highlights the WWP2-p53-p21 axis as a potential novel therapeutic target for CRC.

Lumbar spinal stenosis (LSS) is a common degenerative spinal condition where spinal canal narrowing causes symptoms such as neurogenic claudication, radiculopathy, and lower back pain. While non-operative and surgical approaches yield similar long-term outcomes, surgical intervention—particularly decompression—can provide earlier symptom relief, functional recovery, and fall prevention in selected patients with refractory symptoms. Recent advancements in surgical technologies and image guidance have brought about a paradigm shift in LSS management. Biportal endoscopic spine surgery (BESS) has gained global traction as a minimally invasive alternative to traditional decompression methods, offering superior visualization, less soft tissue damage, shorter hospital stays, and faster recovery. High-quality studies, including randomized controlled trials, have shown promising outcomes for this technique. Furthermore, the integration of navigation systems, robot-assisted instrumentation, and artificial intelligence (AI)-driven diagnostics and surgical planning tools is transforming spinal surgery by enhancing precision in preoperative evaluation and intraoperative execution. These innovations enable accurate targeting, reduce complications, and improve reproducibility across diverse surgical settings. This review provides an updated overview of LSS, covering its pathophysiology, clinical assessment, diagnosis, and treatment. Special emphasis is placed on the growing role of BESS and the transformative impact of digital technologies such as navigation, robotics, and AI in the evolving landscape of spinal stenosis care.

Lycium Radicis Cortex (LRC), derived from the root bark of Lycium chinense Mill., has traditionally been used in East Asian medicine to mitigate heat in the blood and consumptive fever. This study investigates LRC’s effects on skeletal muscle in aged mice subjected to forced exercise and examines the protective properties of its primary constituents, kukoamines A (KA) and B (KB), against dexamethasone (DEX)-induced muscle atrophy. Sixteen-month-old male C57BL/6 mice underwent regular swimming and received oral LRC supplementation for 8 weeks. The effects of KA and KB on muscle atrophy were further explored using C2C12 myotubes treated with DEX. LRC administration significantly enhanced muscle mass, strength, and endurance, while reducing plasma lactate and creatinine levels compared to the control group. LRC also upregulated mRNA expression of MyoD, myogenin, MHC, Akt, and mTOR, and downregulated myostatin, FoxO3a, MuRF1, and atrogin-1 in gastrocnemius and soleus muscles. Furthermore, KA and KB alleviated DEX-induced muscle atrophy in C2C12 myotubes by reducing proteolysis and ROS production, enhancing SOD activity, and improving mitochondrial function. Taken together, LRC may be a useful supplement in exercise-based muscle strengthening and amelioration of muscle disorders, and KA and KB have shown potential as preventive and therapeutic agents for muscle atrophy, indirectly suggesting that the efficacy of LRC is attributed to KA and KB.

Purpose: Chronic myeloid leukemia (CML) in children, adolescents, and young adults is rare and differs from older adults. This study evaluated the outcomes of allogeneic hematopoietic stem cell transplantation (HSCT) in young Korean CML patients during the tyrosine kinase inhibitor (TKI) era. Materials and Methods: A retrospective analysis of 35 CML patients aged < 40 years who underwent allogeneic HSCT from 2009 to 2019 was conducted using Korean Blood and Marrow Transplantation Registry data. Patients were grouped by age < 20 years at HSCT (group 1, n=15) and 20-40 years at HSCT (group 2, n=20). Survival outcomes including overall survival (OS), relapse-free survival (RFS), and event-free survival (EFS) were analyzed using the Kaplan-Meier method. Results: The median time between diagnosis and HSCT was 8.9 months. All the patients achieved engraftment but platelet recovery was significantly slower in group 1 (p=0.034). Acute and chronic graft-versus-host disease occurred in 54.3% and 34.3%, respectively. Five-year OS, RFS, and EFS rates of total patients were 66.8%, 50.8%, and 47.6%, with better OS was observed in group 1 by multivariable analysis (p=0.048). Disease status at HSCT was a significant predictor of OS (p=0.028), RFS (p=0.003), and EFS (p=0.004). Disease progression occurred in 13 out of 35 patients (37.1%); treatment-related mortality accounted for 63.6% of deaths (7 out of 11). Conclusion When performed at a younger age, allogeneic HSCT result in superior outcome in CML. Achieving remission before HSCT is critical for improved outcomes, highlighting the importance of pretransplant remission via optimal TKI strategies and minimal residual disease monitoring.

Purpose: Although human epidermal growth factor receptor 2 (HER2) positivity is prevalent in microinvasive breast cancer (MIBC), data focused on HER2-positive MIBC are limited. We investigated the clinical course and long-term outcomes of HER2-positive MIBC and evaluated the role of adjuvant chemotherapy. Materials and Methods: The study included patients with curatively resected pT1mi pN0 HER2-positive breast cancer between January 2000 and January 2020. Treatments and survival outcomes, including invasive breast cancer-free survival (IBCFS), distant recurrence-free survival (DRFS), and overall survival (OS) were analyzed. Results: The analysis included 799 female patients. The median age was 51 years (range, 23 to 79 years), and 51.6% (n=412) were premenopausal. Multifocality was confirmed in 17.3% (n=138), and estrogen receptor (ER) positivity in 29.8% (n=238). Adjuvant chemotherapy was administered to 17.5% (n=140), with doxifluridine in 96.4% of cases. One patient (0.1%) received trastuzumab. With a median follow-up of 119.0 months (95% confidence interval [CI], 114.0 to 127.0), the 8-year IBCFS, DRFS, and OS were 91.2% (95% CI, 89.1 to 93.3), 97.5% (95% CI, 96.4 to 98.7), and 98.8% (95% CI, 98.0 to 99.6), respectively. No significant differences were observed between patients with and without adjuvant chemotherapy. The lack of differences in IBCFS by chemotherapy was consistent across subgroups, including pre-/postmenopausal patients, grade 1-2/3 tumors, and ER-negative disease. Conclusion A clinically meaningful proportion of HER2-positive MIBC patients experience IBCFS events with long-term follow-up. Adjuvant chemotherapy did not improve survival, potentially due to the use of an outdated, ineffective regimen. The role of modern adjuvant regimens, particularly those incorporating HER2-targeted therapy, warrants further exploration.

Subglottic stenosis (SGS) and tracheal stenosis (TS) are rare conditions that can cause significant breathing difficulties and, if not properly managed, may lead to life-threatening complications. Despite their clinical importance, debate continues regarding the optimal management of adult SGS and TS, and no comprehensive guidelines have been established to date. The Korean Bronchoesophagological Society appointed a task force to develop clinical practice guidelines with the goal of providing evidence-based recommendations for managing SGS and TS in adults. The task force conducted a systematic review of the relevant literature by searching PubMed, Embase, and the Cochrane Library using predefined search terms aligned with key clinical questions. The quality of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach, which also informed the formulation and reporting of the recommendations. The strength of each recommendation reflects the guideline panel’s confidence that the benefits of an intervention outweigh its risks for eligible patients. After drafting the guidelines, feedback was obtained through Delphi questionnaires completed by members of the Korean Bronchoesophagological Society. Ultimately, the committee developed 17 evidence-based recommendations across four categories: initial evaluation, medical management, surgical treatment, and postoperative management and rehabilitation. These guidelines aim to support clinicians in delivering optimal care to adult patients with SGS and TS.

Purpose: Radiotherapy (RT) remains a cornerstone of curative treatment for localized and locally advanced prostate cancer. However, dose escalation to improve tumor control is often constrained by the proximity of the rectum, which increases the risk of gastrointestinal (GI) and genitourinary toxicities. Biodegradable rectal spacers inserted between the prostate and rectum have emerged as an effective approach to reduce rectal radiation exposure. This guideline provides evidence-based recommendations on indications, contraindications, procedural standards, and clinical management for biodegradable rectal spacer insertion during prostate cancer RT. Materials and Methods: This guideline was developed by a multidisciplinary expert panel through a systematic review of the literature, analysis of international guidelines (National Comprehensive Cancer Network, European Association of Urology, American Society for Radiation Oncology), and expert consensus among radiation oncologists, radiologists, and urologists with clinical experience in spacer insertion. The strength of each recommendation and the level of evidence were classified according to the modified GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) system. Results: Spacer insertion is conditionally recommended (Grade C, Level I) for patients receiving definitive external-beam RT without rectal invasion. It reduces the high-dose rectal irradiation volume (V70–75) by >50%, decreases acute GI toxicity, and helps maintain bowel-related quality of life. However, the benefit for late severe toxicity (grade 2 or higher) remains debated in recent meta-analyses. Contraindications include rectal invasion, anatomical inaccessibility, infection, and material hypersensitivity. Procedures should be performed under local anesthesia in a sterile environment by trained physicians. Short-course antibiotics and simulator-based training, including completion of multiple supervised cases, are advised. Conclusion Biodegradable rectal spacer insertion is clinically validated and effective in reducing acute rectal toxicity. Although pivotal trials demonstrated a favorable procedural safety profile, real-world postmarket data include reports of rare but severe procedural complications. This guideline provides standardized recommendations tailored to Korean clinical practice while remaining consistent with international standards, emphasizing the importance of operator training and careful patient selection.

Background: Clopidogrel requires several hours to achieve adequate platelet inhibition. We investigated the association of clopidogrel preloading time with 30-day clinical outcomes and post-procedural troponin elevation in patients with stable angina undergoing elective percutaneous coronary intervention (PCI). Methods: This single-center retrospective cohort study included 1,020 patients with stable angina (clopidogrel-naive) who received 300 mg clopidogrel preloading within 24 hours before elective PCI between 2012 and 2020. Patients were categorized according to clopidogrel preloading-to-balloon time ≤6 hours or >6 hours. The primary endpoint was 30-day major adverse cardiovascular events (MACE), defined as a composite of all-cause death, myocardial infarction, stroke, and any revascularization. Secondary endpoints included serial troponin T changes and troponin T elevation ≥5×, ≥25×, and ≥70× the upper reference limit. Stabilized inverse probability of treatment weighting (IPTW) was used. Results: Thirty-day MACE occurred in five patients (0.49%) and did not differ between the ≤6-hour and >6-hour groups after IPTW (0.5% vs. 0.4%, p=0.754). Post-procedural troponin T levels at 6, 24, and 48 hours were higher in the ≤6-hour group. Patients with shorter preloading-to-balloon times showed higher peak troponin T levels, with the greatest difference at the ≤1-hour cutoff (geometric mean ratio, 2.12; 95% confidence interval, 1.53–2.95; p<0.001) and progressive attenuation at longer cutoffs. Troponin T elevation ≥5× and ≥25× was more frequent in the ≤6-hour group, whereas ≥70× elevation did not differ. Conclusion Clopidogrel preloading ≤6 hours before elective PCI was not associated with increased 30-day MACE but was associated with lower-threshold post-procedural troponin T elevation.

Background: Dual antiplatelet therapy with aspirin and a P2Y12 inhibitor is standard after percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS); however, bleeding risk remains a major concern. Early discontinuation of aspirin due to potent P2Y12 inhibition may mitigate bleeding without increasing thrombotic events. Methods: The ASpirin-FREE therapy after successful percutaneous coronary intervention for acute coronary syndrome (ASFREE) study was an investigator-initiated, single-center, prospective, open-label, single-arm pilot study enrolling patients with ACS who underwent PCI with drug-eluting stents. All patients received a single loading dose of aspirin on the day of the PCI, followed by ticagrelor or prasugrel monotherapy. The primary efficacy endpoint was target vessel failure (TVF) at 12 months. The primary safety endpoint was definite stent thrombosis. Event rates are reported with 95% confidence intervals (CIs). Results: In total, 228 patients were enrolled. TVF occurred in 10 patients (4.4%; 95% CI, 2.1%–7.9%). Definite stent thrombosis was observed in one patient (0.4%; 95% CI, 0.01%–2.4%), with no acute or subacute events. Major bleeding (Bleeding Academic Research Consortium type 3 or 5) occurred in two patients (0.9%; 95% CI, 0.1%–3.1%). Conclusion An aspirin-free strategy following a single loading dose with continuation of potent P2Y12 inhibitor monotherapy was feasible in patients with ACS undergoing PCI and was associated with low rates of thrombotic and major bleeding events. These findings should be regarded as hypothesis-generating and supporting further evaluations in adequately powered randomized controlled trials (CRIS registration: KCT0008182).