Mito Saiseikai General Hospital

BackgroundGastric cancer remains a major cause of cancer-related morbidity and mortality. Despite advances in surgical and perioperative care, prolonged hospitalization continues to strain healthcare systems. Predicting postoperative length of stay (LOS) could support personalized care and efficient resource allocation. Japan's nationwide Diagnosis Procedure Combination (DPC) database provides real-world data for large-scale analysis, but no study has applied machine learning to predict LOS after gastrectomy.MethodsThis retrospective study included 26,097 patients who underwent gastrectomy between 2017 and 2022 at 472 hospitals in Japan. Using XGBoost, we developed a predictive model based on 1,433 admission-time variables extracted from the DPC database. Model performance was evaluated using Root Mean Squared Error (RMSE) and Mean Absolute Error (MAE) in a five-fold cross-validation. SHAP values were used to interpret feature importance.ResultsThe final model achieved an RMSE of 3.74 and MAE of 2.82 days. Key predictors of LOS included surgical procedure (laparoscopic distal gastrectomy and open total gastrectomy), designated cancer hospital, hospital size, peritoneal dissemination, and admission ADL score. SHAP analysis revealed that Laparoscopic distal gastrectomy and higher hospital volume were associated with shorter LOS, while open total gastrectomy was associated with longer LOS.ConclusionsWe developed a machine learning model that predicts postoperative length of stay with an error range of 2–4 days using admission data. This proof-of-concept study demonstrates the feasibility of predicting length of stay from admission data, showing that explainable AI can replicate intuitive patterns in surgical oncology while simultaneously identifying unexpected insights from administrative data. These findings highlight the clinical potential of explainable AI for perioperative workflow optimization.

No effective agents currently exist for treating loss of appetite and apathy in patients with dementia. This multicentre, randomised, comparative study aimed to evaluate the effect and safety of Ninjin'yoeito (NYT) for these symptoms in patients with Alzheimer's disease (AD) or dementia with Lewy Bodies (DLB). A total of 16 sites, including clinics and hospitals, participated in this study. The primary outcome measure was the 12-week change in the loss of appetite score in the 'eating behaviour' subcategory of the Neuropsychiatric Inventory-12 (NPI-12). Secondary outcome measures included changes in food intake, the NPI-12 score, the Japanese Version of the Zarit Caregiver Burden Interview, Vitality Index, Mini-Mental State Examination, Frontal Assessment Battery, body weight, red blood cell count, haemoglobin, albumin, and Controlling Nutritional Status Score. Regarding the efficacy evaluation, 24 and 25 patients were assigned to the NYT and control groups, respectively. Regarding the primary outcome-the change in the loss of appetite score-no significant difference was observed between the two groups at 12 weeks after the start of administration. Among the secondary outcomes, food intake showed a significant increase in the NYT group compared to the control group at both 4 and 12 weeks. In the NYT group, significant decreases were recorded in the NPI-12 total score at 4 and 8 weeks; in depression at 12 weeks; in apathy at 4, 8, and 12 weeks; and in eating behaviour at 4, 8, and 12 weeks. However, these changes were not different from those in the control group. In a post hoc subgroup analysis of participants with a loss of appetite score of ≥ 6, significant decreases from baseline at 8 and 12 weeks were observed in the NYT group compared to the control group. Although the primary endpoint did not reach statistical significance, likely due to insufficient sample size, the NYT group showed a significant improvement in food intake, a secondary outcome measure. Furthermore, exploratory post hoc subgroup analysis suggested that NYT may improve appetite in patients with more severe appetite loss at baseline. These findings indicate the potential role of NYT in appetite improvement in patients with AD or DLB, warranting further investigation.

This study aimed to investigate the incidence and risk factors of thoracolumbar noncontiguous spinal fractures (NSF) in surgically treated older patients with cervical spine injuries and to evaluate their association with functional outcomes. We retrospectively reviewed 115 patients aged ≥ 65 years who underwent surgery for traumatic cervical spine injuries between 2015 and 2025. Thoracolumbar NSF were defined as fractures located at least two vertebral levels away from the cervical injury. Patient background, comorbidities, laboratory data, and imaging findings were collected. Functional outcome was assessed using the Barthel Index (BI) at discharge, with BI ≥ 60 indicating functional independence. Univariate and multivariate logistic regression analyses were performed to identify independent predictors of NSF and BI ≥ 60. Thoracolumbar NSF were observed in 39.1% of patients. High-energy trauma (odds ratio [OR]: 70.7) and pre-existing vertebral fractures (OR: 12.8) were identified as independent positive predictors, whereas the presence of ossification of the posterior longitudinal ligament was negatively associated with NSF (OR: 0.12). In multivariate analysis for BI ≥ 60, higher serum albumin (OR: 10.7) and lower Charlson Comorbidity Index (OR: 0.46) were associated with better functional outcomes, while spinal cord injury was a negative predictor (OR: 0.17). The presence of thoracolumbar NSF was not associated with functional outcome. Thoracolumbar NSF are relatively common in surgically treated older patients with cervical spine injuries. Although they were not linked to worse functional outcomes, their strong association with high-energy trauma and skeletal fragility highlights the need for comprehensive spinal imaging and early risk assessment.

Villitis of unknown etiology (VUE) is a destructive inflammatory lesion of unknown cause in the human placenta. It may be caused by semiallogeneic rejection of fetal tissue by the mother. CD8+ tissue-resident memory T (TRM) cells reside in the peripheral tissues and have an important role in the local defense against reinfection. These cells also contribute to immunopathogenesis under some circumstances and cause local tissue damage and autoimmune disease. In this study, we examine the contribution of CD103+ CD8+ TRM-like cells to the development of VUE. The study included 23 cases of human placenta diagnosed as VUE (high-grade). Double-labeling immunohistochemistry was performed in formalin-fixed paraffin-embedded tissues. CD103+ CD8+ cell accumulation in actively inflamed areas was observed in all cases. The double positivity rate for CD103 and CD8 among the total CD103+ and CD8+ cells was 95% (71-100%) and 58% (18-90%) [median (range)], respectively. This indicated that the vast majority of CD103+ cells in VUE are CD103+ CD8+ TRM-like cells. CD103+ cells exhibited a significantly high proliferative activity based on a Ki-67 labeling index in CD103+ cells of 52% (13-90%). CD103+ cells were aligned beneath E-cadherin+ syncytiotrophoblast cells (subtrophoblast alignment) in the peripheral areas of the VUE lesions. Syncytiotrophoblast cells in VUE were also characterized by the induction of human leukocyte antigens A, B, and C expression. CD103+ cells also expressed granzyme B. Our results suggest that proliferating CD103+ CD8+ TRM-like cells work as cytotoxic effector cells and play an important role in VUE pathogenesis.

The Friedewald equation, commonly used to calculate low-density lipoprotein cholesterol (LDL-C), occasionally yields inaccurate estimations for very-low-density lipoprotein cholesterol, suggesting the need for an alternative method such as the Martin equation. In this study, we aimed to evaluate the discrepancies between the Friedewald and Martin equations, particularly in the context of pathogenic variants associated with familial hypercholesterolemia (FH). We evaluated the discrepancies between LDL-C levels calculated using the Friedewald and Martin equations, and for the presence of pathogenic variants of FH in 53 children with hypercholesterolemia detected through universal lipid screening. Genetic testing revealed pathogenic variants of FH in 24 of the 53 children. Chi-squared tests indicated a significant difference in the presence of pathogenic variants of FH between the "Friedewald ≥ Martin" and "Friedewald < Martin" groups (χ2=11.348, P<0.001). Even in 37 children with LDL-C <180 mg/dL, discrepancies between the equations were still associated with the presence of pathogenic FH variants (Fisher's exact test, P=0.028). Discrepancies in LDL-C levels measured by the Friedewald and Martin equations might serve as a useful predictive marker for identifying pathogenic variants of FH, especially in cases of LDL-C <180 mg/dL, which are often challenging to diagnose.

BackgroundBrugada syndrome (BrS) is an inherited cardiac channelopathy associated with a high risk of sudden cardiac death (SCD) due to ventricular fibrillation (VF). Although implantable cardioverter‐defibrillators (ICDs) are the primary therapy for SCD prevention, the risk stratification of elderly patients with BrS remains unclear. This study aimed to evaluate the incidence and risk factors of life‐threatening arrhythmias in elderly patients with BrS.MethodsWe analyzed 523 patients with BrS (mean age 51 ± 13 years, 497 men) enrolled in the multicenter prospective Japan Idiopathic Ventricular Fibrillation Study. Patients were categorized into the elderly (>60 years, n = 150) and nonelderly (≤60 years, n = 373) groups. Clinical characteristics, programmed electrical stimulation (PES) results, and outcomes, including cardiac events (CEs: VF, fast ventricular tachycardia, or SCD), were compared. Statistical analyses were performed using Kaplan–Meier curves and Cox proportional hazard models.ResultsDuring a mean follow‐up of 106 ± 62 months, 59 patients (11%) experienced CE. The annual CE incidence was lower in the elderly group than in the nonelderly group (0.7% vs. 1.5%, p = 0.016). History of VF independently predicted CE occurrence in elderly patients (hazard ratio: 23.5, p < 0.001). Asymptomatic elderly patients exhibited a negligible risk of CE. PES did not predict CE occurrence in the elderly group.ConclusionsElderly patients with BrS have a better prognosis than nonelderly patients, particularly if they are asymptomatic. A history of VF is a key risk factor for life‐threatening arrhythmias in elderly patients with BrS.

Background and aims Endoscopic mucosal resection (EMR) is a standard preventive method for colorectal cancer. Managing patients on anticoagulants during EMR is challenging because of balancing bleeding and thrombotic risks. Updated guidelines recommend continuing anticoagulants over heparin bridging; however, data on bleeding risks with continuing anticoagulants remain limited. This multicenter prospective study evaluated bleeding rates in patients who continued oral anticoagulants during EMR. Methods Patients on warfarin or direct oral anticoagulants (DOACs) undergoing EMR were enrolled from 12 tertiary hospitals. Warfarin was maintained on the day of EMR, while DOACs were paused on the day of EMR and resumed afterward. Post-EMR mucosal defects were closed with clips per protocol. Adverse events were monitored for 30 days. The primary endpoint was the major bleeding rate, defined as immediate bleeding requiring difficult hemostasis or delayed bleeding necessitating endoscopic intervention. The secondary endpoints were minor bleeding, other adverse events, and differences in bleeding rates between warfarin and DOACs. Results Among 107 patients (341 polyps; mean size = 6.7 mm), major bleeding occurred in five (4.7%) patients (95% confidence interval: 2.0%-10.5%), and all cases were managed endoscopically. Minor bleeding and thromboembolism events occurred in eight (7.5%)patients and one (0.9%) patient, respectively. No significant differences in bleeding rates were observed between warfarin and DOACs. Major bleeding rates were lower than those reported for heparin bridging. Conclusions Continuing anticoagulanttherapy during EMR was associated with a low major bleeding rate (4.7%) and minimal thrombotic events, supporting its safety as an alternative to heparin bridging.

［背景］腹部大動脈瘤（AAA）開腹手術において，欧米のガイドラインでは中枢吻合をできるかぎり腎動脈に近いところで行うことが推奨されているが，日本のガイドラインには記載がない．［目的］低位腎動脈下残存大動脈（Infrarenal Residual Aorta; IRA）の長さと遠隔期の拡大の関連性を検討した．［方法］2002年6月～2016年11月に当院でAAAに対して人工血管置換術を行った100例を対象とした．男性89例，平均年齢70.2±8.2（SD，以下同じ）歳，平均観察期間は8.5±3.3年であった．IRAの長さが2 cm未満のものをS群（n＝24），2 cm以上のものをL群（n＝76）として，術前の低位腎動脈下大動脈径および術直後，術後早期，中期，遠隔期でのIRAの長さと径を計測した．［結果］術前と術直後のIRA径に有意な変化はみられなかった．術前の低位腎動脈下大動脈径はS群23.0［21.0～26.0］mm，L群22.0［20.0～24.5］mmで有意差はなかった．術後早期以降の各期間におけるIRA径は，L群のみで22.0［20.0～26.0］mm，23.0［21.0～27.0］mm，24.0［22.0～28.0］mm，26.0［23.3～32.8］mmと術直後から有意な拡大を示した（p＜0.01）．また，有意差はなかったものの，術前の腎動脈下大動脈径が26 mm以上の群では術後中期以降により大きな拡大傾向がみられた．［結論］IRAの長さと術後IRA径の拡大に関連性が認められた．