Objective: In the da Vinci 5 system, kinematic data on the operator’s console operations are measured automatically. The aim of this study is to determine whether there are differences in the surgical technique data between surgeons with experience with robotic surgery and trainees.Method: Between August 2025 and March 2026, we analyzed 28 cases of anatomical lung resection performed at Shonan Kamakura General Hospital. These cases were divided into groups of experienced surgeons and trainees. We compared kinematic data related to surgical techniques obtained from the da Vinci 5 between the two groups.Results: A significant difference was observed between the groups regarding “time with force”—the time during which forceps equipped with force feedback were operated with a force of 0.5–6.5 N; however, no differences were found in the frequency of camera, hand clutch, and energy pedal use or in the force applied to the forceps. Furthermore, time with force for the fenestrated bipolar forceps operated with the left hand was strongly correlated with console time (correlation coefficient, 0.829).Conclusion: These findings suggest that there may be technical differences in the operation of fenestrated bipolar forceps with the left hand between experienced surgeons and trainees.
Objective Evidence regarding early postoperative outcomes and inflammatory responses after SP robot-assisted radical prostatectomy (RARP) remains limited. This study aims to evaluate early clinical outcomes and surgical stress responses following the complete transition from transperitoneal multiport RARP using the da Vinci Xi system (Xi-RARP) to extraperitoneal SP-RARP. Methods This retrospective single-center study included consecutive patients who underwent RARP by a single surgeon between April 2024 and May 2026 and who underwent Xi-RARP or SP-RARP at Saitama Medical University International Medical Center, Japan. After the introduction of the SP, all subsequent procedures were performed using the SP platform without patient selection. Inverse probability of treatment weighting was used to balance baseline characteristics. Perioperative outcomes, postoperative C-reactive protein (CRP) levels and the neutrophil-to-lymphocyte ratio (NLR), pain scores, cumulative acetaminophen consumption, and early oncologic outcomes were compared between the groups. Effect sizes were weighted mean differences (WMD, SP minus Xi) or odds ratios (ORs, SP versus Xi), reported with robust 95% confidence intervals (CIs). Results In total, 62 patients were included, with 25 undergoing Xi-RARP and 37 undergoing SP-RARP. The baseline covariate balance substantially improved after weighting, although a small residual imbalance remained in the preoperative NLR. No perioperative outcomes were comparable between the groups. There was no statistically significant difference between groups in CRP on postoperative day 1 (WMD, −1.28 mg/dL; 95% CI, −2.62 to 0.06) and postoperative day 3 (WMD, −0.26 mg/dL; 95% CI, −2.65 to 2.14). No statistically significant between-group differences were observed in the postoperative NLR. There was also no statistically significant difference in cumulative acetaminophen consumption between groups through postoperative day 3 (WMD, −429 mg; 95% CI, −862 to 3). Early oncologic outcomes were exploratory, with imprecise estimates. Conclusion Following the complete transition from transperitoneal multiport Xi-RARP to extraperitoneal SP-RARP, no statistically significant between-group differences were observed in terms of perioperative outcomes, early postoperative inflammatory markers levels, or acetaminophen consumption. Early oncologic outcomes were exploratory and limited by the small sample size and imprecise estimates. These findings warrant confirmation in larger prospective studies.
The portal vein (PV), the main vessel that supplies up to 75%–80% of liver blood flow, has long been considered a structure with relatively constant anatomy. Anatomical variants of the PV should be considered important parameters critical to the success of any surgical intervention in the hepatobiliary system. The “standard” anatomy is not present in all patients, with the variant frequency reaching 37%. The most clinically significant variants include main trunk trifurcation, early origin of the right posterior branch, absence of main trunk bifurcation, and origin of right segmental branches from the left PV branch. Anatomical variants not recognized at the preoperative stage increase the risk of massive bleeding, ischemic damage to remaining segments, and iatrogenic bile duct injury. The use of three-dimensional modeling and artificial intelligence allows the minimization of these risks and the transition to personalized surgery. Precise preoperative knowledge of the individual structure of the portal venous system has become an integral component of ensuring surgical safety. Careful consideration of PV anatomy features allows the development of personalized surgical approaches, which are key to successful treatment outcomes in modern high-tech medicine.
Objective The safety and efficacy of robot-assisted colorectal surgery following self-expandable metal stent (SEMS) placement for obstructive colorectal cancer with double-stapling anastomosis remain unclear. This study aimed to compare the short-term outcomes of robot-assisted and laparoscopic surgery in this setting. Methods This single-center retrospective study included patients who underwent minimally invasive surgery with double-stapling anastomosis for obstructive colorectal cancer between June 2018 and July 2025 at Ehime Prefectural Central Hospital, Japan. Patients were divided into robot-assisted surgery (RS) and laparoscopic surgery (LS) groups on the basis of the surgical approach. Short-term outcomes were compared using 1:1 propensity score matching. Results A total of 118 patients (RS, n = 31; LS, n = 87) were included in the study. After matching, 25 patients were included in each group. The operative time was significantly longer in the RS group before matching (246 min [IQR, 201–275 min] vs. 214 min [IQR, 170–255 min], p = 0.003) but was not significantly different after matching (245 min [IQR, 200–270 min] vs. 237 min [IQR, 173–271 min], p = 0.357). After matching, blood loss tended to be lower in the RS group (20 g [IQR, 0–20 g] vs. 50 g [IQR, 0–60 g], p = 0.057), while no significant differences were observed in conversion to laparotomy (0.0% vs. 4.0%, p = 1.000), postoperative length of stay (7 d vs. 8 d, p = 0.910), postoperative complications (12.0% vs. 12.0%, p = 1.000), anastomotic leakage (4.0% vs. 0.0%, p = 1.000), radial margin positivity (4.0% vs. 0.0%, p = 1.000), or 90-day mortality (0.0% vs. 0.0%, p = 1.000). The severity of Clavien–Dindo complications was similar between the groups after matching. Conclusion After propensity score matching, no statistically significant differences in short-term outcomes were observed between the RS and LS in patients with obstructive colorectal cancer who underwent double-stapling anastomosis after SEMS placement. These findings suggest that RS may be a feasible option after SEMS placement, although further studies with larger cohorts are needed.
Objective Pancreatic resection remains one of the most technically demanding abdominal surgery procedures and is associated with substantial perioperative morbidity and long-term mortality. Although minimally invasive pancreatic surgery has been increasingly adopted, its association with longer-term outcomes remains uncertain. This study aimed to develop and internally validate a machine learning model for predicting 1-year mortality after pancreatic resection and to use SHapley Additive exPlanations (SHAP) to explore the contribution of key clinical predictors. Methods This retrospective cohort study was based on the publicly available INSPIRE database. Adult patients who underwent pancreatic resection were included, and the primary outcome was all-cause mortality within 1 year after surgery. After preprocessing, least absolute shrinkage and selection operator (LASSO) regression with class balancing was used to select the most informative predictors. Nine machine learning algorithms were evaluated within a 5-fold cross-validation framework with a synthetic minority over-sampling technique (SMOTE) applied only to the training folds. Model discrimination was primarily assessed using the area under the receiver operating characteristic curve (AUC), while calibration was evaluated by the Brier score and calibration curve. Decision curve analysis (DCA) was used to assess potential clinical utility. The best-performing model was further interpreted using SHAP. Results A total of 414 patients were included, of whom 46 (11.1%) died within 1 year after surgery. LASSO identified 10 core predictors. Among the nine evaluated algorithms, the random forest model achieved the best overall discrimination, with an AUC of 0.722 (95% CI: 0.662–0.777). The model showed acceptable calibration with a Brier score of 0.120 and demonstrated favorable net benefit across a broad range of threshold probabilities in the DCA. SHAP analysis revealed surgical approach, lymphocyte count, and age as the most influential predictors. In the interpretation of the SHAP-based model, the laparoscopic approach appeared to be associated with lower predicted 1-year mortality, and this pattern seemed more pronounced among elderly patients (aged > 65 years). Conclusions This model showed acceptable performance for predicting 1-year mortality after pancreatic resection in the internal validation cohort, and an association between the laparoscopic approach and lower predicted mortality was detected, particularly among elderly patients. These findings may support individualized postoperative risk stratification and generate hypotheses for future prospective studies.
