suggest that some reproductive factors associated with BC differ across ethnicities and time trends, perhaps due to the prevalence of reproductive factors and the baseline hazard of BC.

Purpose: This study compared the efficacy of different irrigation methods for the removal of Ca(OH)2 paste from the root canal. Materials and Methods: The root canals of 75 human mandibular premolars with standardized 15-mm canal lengths were prepared using nickel-titanium rotary files. After drying, the canals were filled with Ca(OH)2 paste. The teeth were divided into five groups: Control group (Group C), conventional irrigation; Group EA, sonic activation (EndoActivator); Groups EQA and EQB, sonic activation (EQ-S with metal tips A and B, respectively); and Group EU, ultrasonic activation (EndoUltra).The Ca(OH)2 paste volume before and after irrigation was measured using micro-computed tomography (CT) images. One specimen from each group was bisected along the long axis, and the canal walls were evaluated at 100× magnification using a scanning electron microscope. Statistical analyses were performed using Kruskal-Wallis and Mann-Whitney U tests. Results: Overall, Ca(OH)2 paste removal was higher in Group EQA than in Group C. In the coronal third, removal rate was higher in Group EQA than in Group C. In the middle third, Groups EQB and EU outperformed Group C. Removal from the apical third was higher in Group EQA than in Group C. All groups showed greater removal from the coronal and middle thirds than from the apical third. Conclusion Sonic and ultrasonic irrigation methods demonstrated higher efficacy than conventional irrigation method for the removal of Ca(OH)2 paste from the root canal. All groups demonstrated better effectiveness in removal from the coronal and middle thirds than from the apical third.

Background: Although patients with malignant melanoma in situ (MIS) have a high survival rate, a risk of recurrence or upstaging remains. Thus, a comprehensive understanding of its prognosis is essential for optimal patient management. Objective: To investigate the clinical characteristics and survival outcomes of Korean patients with MIS. Methods: We retrospectively analyzed the medical records and photographs of patients with MIS treated at a single tertiary center between 2008 and 2021. Clinical features, including diagnosis, treatment, recurrence, and mortality, were examined. Results: A total of 156 patients with MIS were included, with a mean age of 59.3 years. The most common subtype was acral lentiginous melanoma (80.8%). Delayed diagnosis was associated with subungual MIS (SUMis; p ＜0.05). Among the subtypes other than SUMis, 77.3% met three or more of the ABCD criteria for melanoma.Hutchinson’s sign was observed in 67.3% of cases of SUMis. Ulceration was present in only two cases (1.3%).Recurrence occurred in nine patients (5.8%), with four (2.6%) experiencing relapse after 5 years. Upstaging was observed in two patients (1.3%) due to intralymphatic or regional nodal metastasis occurring at 19 and 10 months post-treatment. The 5-year and 10-year melanoma-specific/overall survival rates were 100.0/96.9% and 100.0/89.0%, respectively. Conclusion Although the survival rates of patients with MIS are high, long-term and close follow-up after treatment is essential because of the possibility of late recurrence and rare instances of intralymphatic or regional nodal metastasis. Additionally, the presence of clinical ulceration is highly suggestive of invasive melanoma.

Background: As nationwide government-led whole-genome sequencing (WGS) projects progress, optimizing the clinical integration of large-scale WGS results is crucial. We explored how the initial analysis from Korea’s First WGS Pilot Study for Rare Diseases was applied in clinical practice, and then we reanalyzed the data comprehensively at Samsung Medical Center (SMC) Seoul, Korea. Methods: A prospective cohort study designed to collect WGS data under a Korean national initiative was conducted from August 2020 to December 2021. We focused on patients with rare diseases recruited from 16 university hospitals. The participants included 5,000 individuals (2,200 probands and 2,800 family members). The initial WGS data and diagnostic reference reports (from 682 probands and 484 family members), generated based on the First Korean WGS Pilot Study for Rare Diseases, were subsequently reanalyzed by SMC. Results: The initial analysis of the First Korean WGS Pilot Study data revealed a diagnostic rate of 17%. Upon receiving these results, the SMC conducted two rounds of reanalysis, increasing the diagnostic rate from 15% in the first analysis, to 18% in the second, and finally to 24% in the third (P = 1.6 × 10 −5 ). Key factors in improving the genetic diagnosis included increased detection of novel (likely) pathogenic variants (P = 1.0 × 10 −4 ), improved diagnostic rates with larger family recruitment (P = 0.004), and refined clinical information for more precise genotype–phenotype correlation analysis (40%). Conclusions Although national WGS projects lay a foundation for rare disease diagnosis, hospital-level reanalysis and multidisciplinary collaborations are crucial for optimizing diagnostic outcomes.

Background: Fusion genes are major drivers of acute leukemia. Conventional diagnostics are limited in detecting the diverse fusions included in recently updated acute leukemia classifications. We evaluated the fusion detection performance of RNA sequencing (RNAseq) compared with that of conventional diagnostics in patients with acute leukemia. Methods: We retrospectively obtained the data of 101 patients with acute leukemia who underwent conventional diagnostics (i.e., karyotyping, FISH, or multiplex reverse transcription PCR) at diagnosis at Samsung Medical Center, Seoul, Korea, between September 2022 and September 2023. Whole RNA-seq was performed using the Illumina Stranded mRNA Prep kit (Illumina, San Diego, CA, USA). The concordance, sensitivity, and specificity of RNA-seq for fusion gene detection were compared with those of conventional diagnostics. Results: RNA-seq helped identify 52 fusion genes in 51 (50.5%) of 101 patients, with detection rates of 40.7%, 70.3%, 37.5%, and 50% in acute myeloid leukemia, B-cell acute lymphoblastic leukemia, T-cell acute lymphoblastic leukemia, and mixed-phenotype acute leukemia, respectively. RNA-seq showed 83.3% sensitivity and 80.8% concordance with conventional diagnostics; it missed eight fusions, likely because of low transcript abundance or enhancer hijacking. RNA-seq also helped clarify three previously unspecified rearrangements and detected 12 fusions (21.4%) in 56 cases that tested negative with conventional diagnostics, including four novel (KMT2A::THAP12 , RUNX1::PRPF19 , MLLT10::UBE2L6, and FUS::ZNF362) and three rare (HNRNPH1::ERG, RUNX1::USP42, and ETV6::NCOA2) fusions. Conclusions This was the first study to evaluate the performance of whole RNA-seq in fusion detection in patients with acute leukemia in Korea. Incorporating RNA-seq into diagnostic workflows may facilitate earlier and more precise therapeutic decisions and improve prognostic assessment in patients with acute leukemia.

Objective: Thoracic pedicle screw fixation is technically demanding because of the natural variability in pedicle anatomy, a challenge that is further exacerbated in patients with spinal tumors who often have compromised pedicles. The L-point entry, juxtapedicular, and endplate-parallel trajectory (L-JET) technique was developed to provide a uniform entry point, a predictable screw trajectory, and the capacity to accommodate larger-diameter screws at levels T3–10. This study aimed to evaluate the safety and feasibility of the L-JET technique in comparison with the conventional transpedicular method. Methods: A comparative analysis of consecutively collected data was performed to evaluate outcomes associated with the L-JET technique in patients undergoing surgery for thoracic extradural spinal tumors. The L-point was defined as the intersection of a vertical line along the lateral margin of the facet joint and a horizontal line along the upper edge of the transverse process. The screw trajectory was planned with 30° of medial convergence in the axial plane, creating a juxtapedicular path, and a straightforward trajectory in the sagittal plane. Primary outcome measures included screw diameter, screw length, cortical breach rate, and the need for revision surgery, as assessed using computed tomography scans and medical records. Results: A total of 108 screws were placed in 22 patients using the L-JET technique, while 98 screws were placed in 18 patients using the conventional technique. The L-JET group used significantly larger-diameter screws (6.06±0.65 mm) than the conventional group (5.74±0.80 mm, p=0.02), with no significant difference observed in screw length between groups. Medial cortical breach occurred in one screw in each group, and no supra- or infrapedicular breaches were identified. No screw-related neurovascular complications or revision surgeries occurred in either group. Conclusion The L-JET technique enables consistent screw placement with larger-diameter screws, even in compromised pedicles associated with thoracic spinal tumors, without increasing the risk of complications or the need for revision surgery.

Purpose: Metabolic bariatric surgery (MBS) efficacy and safety is established for older patients, but East Asian data are limited. This study aimed to evaluate the safety and efficacy of MBS by comparing older (≥55 years) and younger (<55 years) East Asian patients with obesity. Methods: This multicenter, retrospective review included 410 patients undergoing MBS from January to December 2019.Patients were stratified into the older group (OG, age ≥55 years; n = 39) and the younger group (YG, age <55 years; n = 371). We compared surgical safety, weight parameters, and comorbidity resolution rates. Results: The OG had lower mean body weight (97.9 ± 16.4 kg vs. 113.2 ± 23.1 kg, P < 0.001) but more comorbidities and lower average ABCD score for type 2 diabetes mellitus (T2DM) remission. Postoperative complication rate (12.8% vs. 7.5%, P = 0.400) and postoperative hospital stay (4.1 ± 1.8 days vs. 4.0 ± 8.9 days, P = 0.773) showed no significant differences.At 12 months, the percentage of total weight loss was significantly lower in the OG (23.7 ± 6.9% vs. 27.8 ± 8.4%, P = 0.014).Remission rates for T2DM (47.6% vs. 80.5%, P < 0.001), hypertension (34.6% vs. 57.5%, P = 0.073), and dyslipidemia (12.5% vs. 44.4%, P = 0.012) were also lower in the OG, yet still demonstrated clinically meaningful metabolic improvement. Conclusion MBS is a safe and effective treatment for older East Asians with obesity, offering substantial comorbidity resolution despite achieving a lower weight loss compared to the younger patients.

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.