Oncological long-term outcomes of laparoscopic versus open gastrectomy for cT3-4 gastric cancer at surgical staging: a propensity-score matched cohort study.

BACKGROUND: The oncological efficacy of laparoscopic surgery for advanced gastric cancer (AGC) has been evaluated by several randomized trials. However, the inclusion of earlier-stage disease was a limitation in previous studies. METHODS: Patients with cT3-4 gastric cancer, determined by surgical staging to minimize migration of earlier stages, treated at a tertiary cancer center from 2009 to 2018 were included. Based on the surgical approach, the patients were divided into two groups: the laparoscopic gastrectomy (LG) and the open gastrectomy (OG) and matched for age, sex, macroscopic appearance (type 4 or non-type 4), body mass index, estimated tumor size, clinical stage T3'T4, clinical N stage, pathologic T stage (T3 or T4), and type of surgery (total or distal gastrectomy). RESULTS: 588 patients (221 LG, 367 OG) were included in the analysis. After 1:1 propensity-score matching, 386 patients (193 LG, 193 OG) were assigned for analysis. In the LG group, operation time was longer with lower blood loss. The incidence of postoperative complications (≥ grade III) did not differ significantly between the groups (OG: 8.3%, vs. LG: 9.3%). Overall survival (OS) was longer in the LG group (5-year OS: 79.3 vs. 73% HR 0.66, 95% CI 0.44-0.99, P = 0.0497). Relapse-free survival (RFS) did not show a statistical difference (5-year RFS: 69.5 vs. 68.7 HR 0.88, 95% CI 0.62-1.26, P = 0.487). Subgroup analysis for OS also demonstrated equivalent outcomes. CONCLUSION: LG demonstrates comparable safety and efficacy to OG for advanced gastric cancer at surgical staging, with similar rates of severe complications and long-term oncological outcomes. Further research is needed to validate these findings, particularly for total gastrectomy and for patients from Western populations.

HaptoFloater: Visuo-Haptic Augmented Reality by Embedding Imperceptible Color Vibration Signals for Tactile Display Control in a Mid-Air Image.

We propose HaptoFloater, a low-latency mid-air visuo-haptic augmented reality (VHAR) system that utilizes imperceptible color vibrations. When adding tactile stimuli to the visual information of a mid-air image, the user should not perceive the latency between the tactile and visual information. However, conventional tactile presentation methods for mid-air images, based on cameradetected fingertip positioning, introduce latency due to image processing and communication. To mitigate this latency, we use a color vibration technique; humans cannot perceive the vibration when the display alternates between two different color stimuli at a frequency of 25 Hz or higher. In our system, we embed this imperceptible color vibration into the mid-air image formed by a micromirror array plate, and a photodiode on the fingertip device directly detects this color vibration to provide tactile stimulation. Thus, our system allows for the tactile perception of multiple patterns on a mid-air image in 59.5 ms. In addition, we evaluate the visual-haptic delay tolerance on a mid-air display using our VHAR system and a tactile actuator with a single pattern and faster response time. The results of our user study indicate a visual-haptic delay tolerance of 110.6 ms, which is considerably larger than the latency associated with systems using multiple tactile patterns.

Quantification of Gremlin 1 throughout the tumor stroma using whole slide imaging and its clinicopathological significance in gastric cancer.

Gremlin 1 (GREM1) is an antagonist of bone morphogenetic protein (BMP). GREM1 is expressed in the stromal cells of various carcinomas and promotes tumor progression by suppressing BMP signaling. We designed this study to establish an evaluation strategy for GREM1 expression, focusing on the tumor stroma, and to examine its clinicopathological significance in gastric cancer (GC) progression. We employed RNA in situ hybridization (ISH) to evaluate the prognostic value of GREM1 expression in a cohort of 104 surgically resected GC cases and assessed ISH scores according to previous reports. GREM1 expression was observed in tumor stromal cells, including fibroblasts. We defined GREM1-positive cells as those expressing ISH score ≥ 3 and quantified the number of GREM1-positive cells using image analysis software. We examined the relationship between the number of GREM1-positive cells in the tumor stroma and clinicopathological features. The number of GREM1-positive cells per tumor stroma ranged from 0 to 714.7 cells/mm2 (median, 1.65 cells/mm2). We divided the 104 GC cases into GREM1-High and GREM1-Low expression groups based on the abovementioned median value. GREM1-High expression group was significantly associated with a more advanced pT grade, pN grade, lymphatic invasion, and venous invasion. Kaplan-Meier analysis showed significantly poorer survival in the GREM1-High expression group than in the GREM1-Low expression group. These results indicated that GREM1 expression in GC is localized in tumor stromal cells, and that high GREM1 expression in the tumor stroma could be a poor prognostic factor.

Surgical step recognition in laparoscopic distal gastrectomy using artificial intelligence: a proof-of-concept study.

PURPOSE: Laparoscopic distal gastrectomy (LDG) is a difficult procedure for early career surgeons. Artificial intelligence (AI)-based surgical step recognition is crucial for establishing context-aware computer-aided surgery systems. In this study, we aimed to develop an automatic recognition model for LDG using AI and evaluate its performance. METHODS: Patients who underwent LDG at our institution in 2019 were included in this study. Surgical video data were classified into the following nine steps: (1) Port insertion; (2) Lymphadenectomy on the left side of the greater curvature; (3) Lymphadenectomy on the right side of the greater curvature; (4) Division of the duodenum; (5) Lymphadenectomy of the suprapancreatic area; (6) Lymphadenectomy on the lesser curvature; (7) Division of the stomach; (8) Reconstruction; and (9) From reconstruction to completion of surgery. Two gastric surgeons manually assigned all annotation labels. Convolutional neural network (CNN)-based image classification was further employed to identify surgical steps. RESULTS: The dataset comprised 40 LDG videos. Over 1,000,000 frames with annotated labels of the LDG steps were used to train the deep-learning model, with 30 and 10 surgical videos for training and validation, respectively. The classification accuracies of the developed models were precision, 0.88; recall, 0.87; F1 score, 0.88; and overall accuracy, 0.89. The inference speed of the proposed model was 32 ps. CONCLUSION: The developed CNN model automatically recognized the LDG surgical process with relatively high accuracy. Adding more data to this model could provide a fundamental technology that could be used in the development of future surgical instruments.

Feasibility of laparoscopic/robot-assisted surgery for Borrmann type 4 gastric cancer: a comparison study with conventional open surgery.

BACKGROUND: Laparoscopic surgery for early gastric cancer is regarded as a standard of care because of robust evidences obtained by several phase-III trials. Furthermore, the efficacy of laparoscopic radical surgery for advanced gastric cancer has been also reported. Meanwhile, the feasibility of laparoscopic surgery for Bormann type 4 gastric cancer, special type with unfavorable prognosis, remains unclear since excluded from eligibility of these trials. METHODS: This study included 100 patients with type 4 gastric cancer who underwent laparoscopic/robot-assisted (minimally invasive surgery (MIS) group; n = 32) or open (Open group; n = 68) curative surgery between 2008 and 2021. After propensity score matching, 30 patients in each group were extracted for analysis. Clinical data, including surgical and midterm survival outcomes, were retrospectively compared between the two groups. RESULTS: Incidences of postoperative complication (≥ Clavien-Dindo grade III) were recorded in 23.3% in the MIS group and 13.3% in the Open group, but no statistical significance was demonstrated (P = 0.50). The 3-year overall survival rate in the MIS group was better than that in the Open group (80.2% vs. 53.5%, log-rank, P = 0.03). The trend of recurrence site was similar. Multivariate analysis showed that adjuvant chemotherapy was an independent favorable prognostic factor (hazard ratio, 0.33, 95% confidence interval 0.11-0.93) for overall survival. MIS was indicated as a favorable prognostic factor (hazard ratio, 0.39, 95% confidence interval 0.39-1.07), but without statistical difference. CONCLUSION: While multidisciplinary treatment is mainstay of treatment because of the poor prognosis of this disease, minimally invasive surgery may play an important role in treatment if appropriate patient selection is done. Further analyses with larger sample size are necessary to reach a final conclusion regarding oncological efficacy.

Definitive chemoradiotherapy induces T-cell-inflamed tumor microenvironment in unresectable locally advanced esophageal squamous cell carcinoma.

BACKGROUND: Chemoradiotherapy (CRT) modulates the tumor immune microenvironment of multiple cancer types, including esophageal cancer, which potentially induces both immunogenicity and immunosuppression by upregulating the presentation of tumor-specific antigens and immune checkpoint molecules in tumors, respectively. The prognostic effects of immune modification by CRT in esophageal squamous cell carcinoma (ESCC) remain controversial because of the lack of detailed immunological analyses using paired clinical specimens before and after CRT. We aimed to clarify the immunological changes in the tumor microenvironment caused by CRT and elucidate the predictive importance of clinical response and prognosis and the rationale for the necessity of subsequent programmed cell death protein 1 (PD-1) inhibitor treatment. METHODS: In this study, we performed a comprehensive immunological analysis of paired biopsy specimens using multiplex immunohistochemistry before and after CRT in patients with unresectable locally advanced ESCC. RESULTS: CRT significantly increased the intra-tumoral infiltration and PD-1 expression of CD8+ T cells and conventional CD4+ T cells but decreased those of regulatory T cells and the accumulation of tumor-associated macrophages. Multivariate analysis of tumor-infiltrating T-cell phenotypes revealed that the density of PD-1+CD8+ T cells in the tumor after CRT could predict a confirmed complete response and favorable survival. CONCLUSIONS: This study showed that CRT improved the immunological characteristics of unresectable locally advanced ESCC and identified the density of PD-1+CD8+ T cells as a predictive factor for prognosis. This finding supports the rationale for the necessity of subsequent PD-1 inhibitor treatment.

Comparison of the survival outcomes between retrocolic and antecolic Roux-en-Y reconstruction after gastrectomy for gastric cancer.

Background: There are two methods of Roux-en-Y (RY) reconstruction after gastrectomy: the antecolic route (ACR) and retrocolic route (RCR). There is no evidence to support that the ACR achieves comparable long-term survival. Methods: This was a multi-center historical cohort study. Patients diagnosed with clinical T3/4a and any N stage who underwent open gastrectomy and R0 resection for gastric adenocarcinoma between January 2006 and December 2012 were enrolled. The primary outcome was the hazard ratio of ACR for overall survival, with adjustment for confounding factors by propensity score matching, and a Cox proportional hazards model. Results: A total of 1758 eligible patients were identified from the database. After matching, 410 patients in the ACR and RCR groups were included in the final analysis. The adjusted hazard ratio (95% CI) for ACR was 1.148 (0.870-1.492). The five-year survival rates in the ACR and RCR groups were 74.3% (69.5-78.4) and 77.3% (72.3-81.2), respectively. The short-term surgical outcomes of the two groups did not differ to a statistically significant extent. Conclusion: The route used to lift the jejunum in RY reconstruction did not affect the incidence of long-term survival or postoperative complications. The ACR and RCR are both acceptable options for RY reconstruction during gastric cancer surgery.

Failure mechanisms data analysis during tension of additively manufactured Ti-6Al-4V alloy reinforced with nano-zirconia particles: Investigations of the crack path.

The data presented here aim to show how to analyze crack propagation of a novel metallic matrix composite of Ti-6Al-4V reinforced with 1 wt.% nano-yttria-stabilized zirconia processed by laser powder bed fusion technology. The data was acquired via microstructural observations and electron backscatter diffraction (EBSD) analyses after the quasistatic tensile tests at room temperature. The overall crack path configuration based on the fracture surface observation by scanning electron microscopy (SEM) was first operated, presenting two main regions: (i) local inclined planes (hereafter denoted as "stair-like"), and (ii) region in accordance with the theoretical mode I fracture plane. Thereafter, a series of EBSD data set on a surface obtained after longitudinal cut off operation on one failed piece was conducted at three distinct positions: (i) in the stair-like configuration region, (ii) in the mode I fracture region, and (iii) in the region where the crack path made his transition between these two mechanisms. Since the EBSD data sets were not prone to any post-processing filtering operation, comparison of the observed mechanism with other Ti-6Al-4V alloy processed by additive manufacturing (AM) technology can be easily carried out.

Early endpoints of a randomized phase II trial of preoperative chemotherapy with S-1/CDDP with or without trastuzumab followed by surgery for HER2-positive resectable gastric or esophagogastric junction adenocarcinoma with extensive lymph node metastasis: Japan Clinical Oncology Group study JCOG1301C (Trigger Study).

BACKGROUND: This randomized phase II study explored the superiority of trastuzumab plus S-1 plus cisplatin (SP) over SP alone as neoadjuvant chemotherapy (NAC) for HER2-positive resectable gastric cancer with extensive lymph node metastasis. METHODS: Eligible patients with HER2-positive gastric or esophagogastric junction cancer and extensive lymph node metastasis were randomized to receive three or four courses of preoperative chemotherapy with SP (arm A) or SP plus trastuzumab (arm B). Following gastrectomy, adjuvant chemotherapy with S-1 was administered for 1 year in both arms. The primary endpoint was overall survival, and the sample size was 130 patients in total. The trial is registered with the Japan Registry of Clinical Trials, jRCTs031180006. RESULTS: This report elucidates the early endpoints, including pathological findings and safety. The study was terminated early due to slow patient accruals. In total, 46 patients were allocated to arm A (n = 22) and arm B (n = 24). NAC was completed in 20 patients (91%) in arm A and 23 patients (96%) in arm B, with similar incidences of grade 3-4 hematological and non-hematological adverse events. Objective response rates were 50% in arm A and 84% in arm B (p = 0·065). %R0 resection rates were 91% and 92%, and pathological response rates (≥ grade 1b in Japanese classification) were 23% and 50% (p = 0·072) in resected patients, respectively. CONCLUSIONS: Trastuzumab can be safely added to platinum-containing doublet chemotherapy as NAC, and it has the potential to contribute to higher antitumor activity against locally advanced, HER2-positive gastric or esophagogastric junction cancer with extensive nodal metastasis.

A nonrandomized controlled trial: long-term outcomes of LATG/LAPG for cStage I gastric cancer: Japan Clinical Oncology Group Study JCOG1401.

BACKGROUND: A previous report confirmed the safety of laparoscopy-assisted total and proximal gastrectomies (LATG and LAPG) (JCOG1401). This report demonstrates the 5-year relapse-free survival (RFS) and overall survival (OS) after long-term follow-up to confirm the efficacy of these surgical methods as key secondary endpoints for cStage I gastric cancer. METHODS: This study enrolled patients who had histologically proven gastric adenocarcinoma and were diagnosed with clinical T1N0, T1N(+), or T2N0 tumors according to the 14th edition of the Japanese Classification of Gastric Carcinoma (3rd English edition). RESULTS: Between April 2015 and February 2017, 246 patients were enrolled, although one patient was excluded because of misregistration. Meticulous follow-up was continued for > 5 years for each patient, and the data were analyzed in March 2022. The 5-year RFS was 90.0% (95% confidence interval [CI] 85.5-93.2%), and the 5-year OS was 91.2% (95% CI 86.9-94.2%) in all enrolled patients. Grade 3 or 4 late postoperative complications were detected in 12.7% of patients. CONCLUSIONS: This single-arm study showed that the long-term outcomes of LATG/LAPG for cStage I gastric cancer were acceptable, which is considered one of the standard treatments when performed by experienced surgeons. Trail registration UMIN000017155 ( http://www.umin.ac.jp/ctr/ ).

Automatic surgical phase recognition-based skill assessment in laparoscopic distal gastrectomy using multicenter videos.

BACKGROUND: Gastric surgery involves numerous surgical phases; however, its steps can be clearly defined. Deep learning-based surgical phase recognition can promote stylization of gastric surgery with applications in automatic surgical skill assessment. This study aimed to develop a deep learning-based surgical phase-recognition model using multicenter videos of laparoscopic distal gastrectomy, and examine the feasibility of automatic surgical skill assessment using the developed model. METHODS: Surgical videos from 20 hospitals were used. Laparoscopic distal gastrectomy was defined and annotated into nine phases and a deep learning-based image classification model was developed for phase recognition. We examined whether the developed model's output, including the number of frames in each phase and the adequacy of the surgical field development during the phase of supra-pancreatic lymphadenectomy, correlated with the manually assigned skill assessment score. RESULTS: The overall accuracy of phase recognition was 88.8%. Regarding surgical skill assessment based on the number of frames during the phases of lymphadenectomy of the left greater curvature and reconstruction, the number of frames in the high-score group were significantly less than those in the low-score group (829 vs. 1,152, P < 0.01; 1,208 vs. 1,586, P = 0.01, respectively). The output score of the adequacy of the surgical field development, which is the developed model's output, was significantly higher in the high-score group than that in the low-score group (0.975 vs. 0.970, P = 0.04). CONCLUSION: The developed model had high accuracy in phase-recognition tasks and has the potential for application in automatic surgical skill assessment systems.

Surgical Techniques and Related Perioperative Outcomes After Robot-assisted Minimally Invasive Gastrectomy (RAMIG): Results From the Prospective Multicenter International Ugira Gastric Registry.

OBJECTIVE: To gain insight in global practice of RAMIG and evaluated perioperative outcomes using an international registry. BACKGROUND: The techniques and perioperative outcomes of robot-assisted minimally invasive gastrectomy (RAMIG) for gastric cancer vary substantially in literature. METHODS: Prospectively registered RAMIG-cases for gastric cancer (≥10 per center) were extracted from 25 centers in Europe, Asia and South-America. Techniques for the resection, reconstruction, anastomosis and lymphadenectomy were analyzed, and related to perioperative surgical and oncological outcomes. Complications were uniformly defined by the Gastrectomy Complications Consensus Group. RESULTS: Between 2020-2023, 759 patients underwent total (n=272), distal (n=465) or proximal (n=22) gastrectomy (RAMIG). After total gastrectomy with Roux-en-Y-reconstruction, anastomotic leakage rates were 8% with hand-sewn (n=9/111) and 6% with linear stapled anastomoses (n=6/100). After distal gastrectomy with Roux-en-Y (67%) or Billroth-II-reconstruction (31%), anastomotic leakage rates were 3% with linear stapled (n=11/433) and 0% with hand-sewn anastomoses (n=0/26). Extent of lymphadenectomy consisted of D1+ (28%), D2 (59%) or D2+ (12%). Median nodal harvest yielded 31 nodes [IQR 21-47] after total and 34 nodes [IQR 24-47] after distal gastrectomy. R0-resection rates were 93% after total and 96% distal gastrectomy. Hospital stay was 9 days after total and distal gastrectomy, and was 3 days shorter without perianastomotic drains versus routine drain placement. Postoperative 30-day mortality was 1%. CONCLUSIONS: This large multicenter study provided a worldwide overview of current RAMIG-techniques with their respective perioperative outcomes. These outcomes demonstrated high surgical quality, set a quality standard for RAMIG and can be considered an international reference for surgical standardization.

Randomized controlled phase III trial to investigate superiority of robot-assisted gastrectomy over laparoscopic gastrectomy for clinical stage T1-4aN0-3 gastric cancer patients (JCOG1907, MONA LISA study): a study protocol.

BACKGROUND: Laparoscopic gastrectomy (LG) is considered a standard treatment for clinical stage I gastric cancer. Nevertheless, LG has some drawbacks, such as motion restriction and difficulties in spatial perception. Robot-assisted gastrectomy (RG) overcomes these drawbacks by using articulated forceps, tremor-filtering capability, and high-resolution three-dimensional imaging, and it is expected to enable more precise and safer procedures than LG for gastric cancer. However, robust evidence based on a large-scale randomized study is lacking. METHODS: We are performing a randomized controlled phase III study to investigate the superiority of RG over LG for clinical T1-2N0-2 gastric cancer in terms of safety. In total, 1,040 patients are planned to be enrolled from 46 Japanese institutions over 5 years. The primary endpoint is the incidence of postoperative intra-abdominal infectious complications, including anastomotic leakage, pancreatic fistula, and intra-abdominal abscess of Clavien-Dindo (CD) grade ≥ II. The secondary endpoints are the incidence of all CD grade ≥ II and ≥ IIIA postoperative complications, the incidence of CD grade ≥ IIIA postoperative intra-abdominal infectious complications, relapse-free survival, overall survival, the proportion of RG completion, the proportion of LG completion, the proportion of conversion to open surgery, the proportion of operation-related death, and short-term surgical outcomes. The Japan Clinical Oncology Group Protocol Review Committee approved this study protocol in January 2020. Approval from the institutional review board was obtained before starting patient enrollment in each institution. Patient enrollment began in March 2020. We revised the protocol to expand the eligibility criteria to T1-4aN0-3 in July 2022 based on the results of randomized trials of LG demonstrating non-inferiority of LG to open surgery for survival outcomes in advanced gastric cancer. DISCUSSION: This is the first multicenter randomized controlled trial to confirm the superiority of RG over LG in terms of safety. This study will demonstrate whether RG is superior for gastric cancer. TRIAL REGISTRATION: The protocol of JCOG1907 was registered in the UMIN Clinical Trials Registry as UMIN000039825 ( http://www.umin.ac.jp/ctr/index.htm ). Date of Registration: March 16, 2020. Date of First Participant Enrollment: April 1, 2020.

Evaluating the identification of the extent of gastric cancer by over-1000 nm near-infrared hyperspectral imaging using surgical specimens.

Significance: Determining the extent of gastric cancer (GC) is necessary for evaluating the gastrectomy margin for GC. Additionally, determining the extent of the GC that is not exposed to the mucosal surface remains difficult. However, near-infrared (NIR) can penetrate mucosal tissues highly efficiently. Aim: We investigated the ability of near-infrared hyperspectral imaging (NIR-HSI) to identify GC areas, including exposed and unexposed using surgical specimens, and explored the identifiable characteristics of the GC. Approach: Our study examined 10 patients with diagnosed GC who underwent surgery between 2020 and 2021. Specimen images were captured using NIR-HSI. For the specimens, the exposed area was defined as an area wherein the cancer was exposed on the surface, the unexposed area as an area wherein the cancer was present although the surface was covered by normal tissue, and the normal area as an area wherein the cancer was absent. We estimated the GC (including the exposed and unexposed areas) and normal areas using a support vector machine, which is a machine-learning method for classification. The prediction accuracy of the GC region in every area and normal region was evaluated. Additionally, the tumor thicknesses of the GC were pathologically measured, and their differences in identifiable and unidentifiable areas were compared using NIR-HSI. Results: The average prediction accuracy of the GC regions combined with both areas was 77.2%; with exposed and unexposed areas was 79.7% and 68.5%, respectively; and with normal regions was 79.7%. Additionally, the areas identified as cancerous had a tumor thickness of >2 mm. Conclusions: NIR-HSI identified the GC regions with high rates. As a feature, the exposed and unexposed areas with tumor thicknesses of >2 mm were identified using NIR-HSI.

[Treatment Strategy for Oligometastatic Gastric Cancer].

Oligometastases are generally defined as a small number of metastases(2-3 or less)in 1 or 2 organs. Oligometastases are rare in gastric cancer because they are often associated with peritoneal dissemination, but gastric cancer patients experience a relatively high incidence of para-aortic lymph node and liver metastases in particular. The Sixth Edition of the Japanese Gastric Cancer Treatment Guidelines weakly recommends surgical resection after medical therapy for a small number of para-aortic lymph node metastases confined to No. 16a2/b1 and a single liver metastasis in the absence of other non-curative resection factors. In Japan, the common treatment strategy is surgical resection after drug therapy, often with the addition of adjuvant chemotherapy after surgery as well. Preoperative drug therapy is generally administered for 3-4 months. Surgical resection has been shown to be relatively safe in experienced centers. Prospective clinical trials are underway in Japan and overseas to establish a higher level of evidence.

Artificial Intelligence in Surgery and Its Potential for Gastric Cancer.

Artificial intelligence (AI) has made significant progress in recent years, and many medical fields are attempting to introduce AI technology into clinical practice. Currently, much research is being conducted to evaluate that AI can be incorporated into surgical procedures to make them safer and more efficient, subsequently to obtain better outcomes for patients. In this paper, we review basic AI research regarding surgery and discuss the potential for implementing AI technology in gastric cancer surgery. At present, research and development is focused on AI technologies that assist the surgeon's understandings and judgment during surgery, such as anatomical navigation. AI systems are also being developed to recognize in which the surgical phase is ongoing. Such a surgical phase recognition systems is considered for effective storage of surgical videos and education, in the future, for use in systems to objectively evaluate the skill of surgeons. At this time, it is not considered practical to let AI make intraoperative decisions or move forceps automatically from an ethical standpoint, too. At present, AI research on surgery has various limitations, and it is desirable to develop practical systems that will truly benefit clinical practice in the future.

Effects of correction rate for severe hyponatremia in the intensive care unit on patient outcomes.

PURPOSE: Limited evidence exists regarding outcomes associated with different correction rates of severe hyponatremia. MATERIALS AND METHODS: This retrospective cohort analysis employed a multi-center ICU database to identify patients with sodium ≤120 mEq/L during ICU admission. We determined correction rates over the first 24 h and categorized them as rapid (> 8 mEq/L/day) or slow (≤ 8 mEq/L/day). The primary outcome was in-hospital mortality. Secondary outcomes included hospital-free days, ICU-free days, and neurological complications. We used inverse probability weighting for confounder adjustment. RESULTS: Our cohort included 1024 patients; 451 rapid and 573 slow correctors. Rapid correction was associated with lower in-hospital mortality (absolute difference: -4.37%; 95% CI, -8.47 to -0.26%), longer hospital-free days (1.80 days; 95% CI, 0.82 to 2.79 days), and longer ICU-free days (1.16 days; 95% CI, 0.15 to 2.17 days). There was no significant difference in neurological complications (2.31%; 95% CI, -0.77 to 5.40%). CONCLUSION: Rapid correction (>8 mEq/L/day) of severe hyponatremia within the first 24 h was associated with lower in-hospital mortality and longer ICU and hospital-free days without an increase in neurological complication. Despite major limitations, including the inability to identify the chronicity of hyponatremia, the results have important implications and warrant prospective studies.

Advantages of robotic gastrectomy for overweight patients with gastric cancer: a comparison study of robotic gastrectomy and conventional laparoscopic gastrectomy.

PURPOSE: A high body mass index (BMI) generally increases the risk of postoperative complications because of the intraperitoneal adipose tissue. Robotic gastrectomy (RG) decreases the surgical difficulty of conventional laparoscopic gastrectomy (LG) for these patients. We conducted the present study to identify the advantages of RG over LG for overweight patients. METHODS: We reviewed clinical data on patients who underwent either LG or RG at the National Cancer Center Hospital East between January, 2014 and May, 2022. RESULTS: The 1298 patients eligible patients were divided into a non-overweight cohort (n = 996) (LG, n = 818; RG, n = 178) and an overweight cohort (n = 302) (LG, n = 250; RG, n = 52) according to a BMI cut-off of 25 kg/m2. In the overweight cohort, the RG group had a lower incidence of grade ≥ III postoperative complications (0.0 vs. 8.8%, p = 0.01) and grade ≥ II postoperative complications (11.5 vs. 22.0%, p = 0.12) than the LG group. Multivariate analysis identified that RG was significantly associated with a lower incidence of grade ≥ II postoperative complications in the overweight cohort (odds ratio, 0.33; 95% confidence interval, 0.12-0.87; p = 0.02). CONCLUSIONS: RG may reduce the risk of postoperative complications, compared with conventional LG, in overweight patients.