内田 雄一郎

BACKGROUND: Late biliary complications, consisting of anastomotic stricture and cholangitis, are known to impair long-term quality of life and significantly impact patient outcomes following robot-assisted pancreaticoduodenectomy (RPD). The role of stent placement in HJ remains debatable. This study aimed to investigate the incidence of late biliary complications and the impact of stent placement on long-term outcomes after RPD. METHODS: This retrospective observational study included patients who underwent RPD from November 2009 to April 2024 at two institutions. Patients were categorized into no-stent, internal stent, and external stent groups. The incidence of late biliary complications was analyzed with Kaplan-Meier estimates and Cox proportional hazards models. RESULTS: The analysis included 157 patients. Late biliary stricture occurred in 20 (13%) cases, with 17 (11%) cases being nontumor-related. No cases of late biliary stricture were observed in patients with a preoperative bile duct diameter of ≥ 15 mm. Internal stent placement was determined as an independent protective factor against late biliary stricture compared to no-stent placement among patients with a bile duct diameter of < 15 mm (hazard ratio: 0.310, 95% confidence interval: 0.096-0.999, p = 0.050). Spontaneous dislocation of internal stents occurred in 71% of cases at 6 months postoperatively. The incidence of postoperative late cholangitis in the internal stent group was 17% (15/89), which was not significantly different compared with the no-stent group (30%, 12/40; p = 0.237). External stent placement prolonged hospitalization and was not superior in biliary complication prevention. CONCLUSIONS: Internal stent placement may decrease the incidence of late biliary stricture after RPD and should be considered a preferred strategy for biliary reconstruction, except in cases with significant bile duct dilatation.

BACKGROUND: Partial pancreatectomies for intraductal papillary mucinous neoplasms (IPMN) often leave a dilated main pancreatic duct (MPD). However, its impact on the development of remnant pancreatic lesions is unknown. METHODS: Medical records of consecutive patients who underwent partial pancreatectomy for noninvasive or microinvasive IPMN with dilated MPD on preoperative imaging between April 2007 and March 2023 at two tertiary referral centers in Japan were retrospectively reviewed. A dilated remnant MPD (DRM) was defined as an MPD diameter of the expected remnant pancreas of ≥5 mm. The clinically significant remnant pancreatic lesion (CSRPL) was defined as a remnant pancreatic lesion which requires intervention. RESULTS: A total of 172 patients (106 males and 66 females) were analyzed. Preoperatively, 132 patients (76.7 %) had mixed-type IPMN and 40 (23.1 %) had main duct IPMN. Among them, 16 patients (9.3 %) had CSRPL at 1569 days (median; range, 120-5503 days) after the initial surgery. In the preoperative imaging analysis, 104 patients (60.5 %) had DRM. The univariate analysis revealed that high-grade or micro-invasive pathology (p = 0.013) was significantly associated with CSRPL, whereas DRM was inversely associated with CSRPL (p = 0.021). The multivariate analysis revealed that the trends of DRM (p = 0.002) and high-grade/micro-invasive pathology (p = 0.003) remained significant. CONCLUSIONS: Leaving a dilated MPD did not increase but instead inversely associated with the incidence of CSRPL after IPMN resection. It was suggested that preserving the pancreas, including the dilated MPD, is oncologically safe if the lesion of interest can be resected.

BACKGROUND: The use of the hinotori™ Surgical System (hinotori) in distal pancreatectomy (DP) is new compared to the da Vinci™ Surgical System (DVSS). The hinotori is equipped with mechanisms distinct from those of DVSS, and comprehensive reports detailing the surgical techniques and outcomes associated with hinotori in DP (hinotori-DP) are lacking. This study aimed to compare the outcomes of DP using the hinotori and DVSS (Xi system), focusing on differences in settings and techniques between the two methods. METHODS: This study retrospectively investigated consecutive patients who underwent robotic DP from April 2010 (the introduction of robotic DP at our institute) to July 2024. The analysis excluded patients who underwent spleen-preserving procedures or procedures performed using robotic platform other than hinotori or daVinci Xi. The hinotori-DP cases were compared with those performed using DVSS (DVSS-DP). The techniques used in hinotori-DP were examined in more detail. RESULTS: A total of 75 robotic DP cases (11 with hinotori and 64 with DVSS) were analyzed in this study. Different port configurations and techniques, including a lesser curvature approach, were used in the hinotori-DP compared to DVSS-DP. The operation time was relatively shorter in the hinotori-DP group (299 vs. 366 min, p = 0.095), and the postoperative complication rates were comparable (pancreatic fistula: 27 % vs. 30 %, p = 0.871; Clavien-Dindo Grade ≥3a complications: 18 % vs. 19 %, p = 0.964) between the two groups. CONCLUSION: The hinotori-DP can be safely performed by focusing on the unique characteristics of the hinotori surgical system.

BACKGROUND: Although minimally invasive distal pancreatectomy (MIDP) is considered a standard approach it still presents a non-negligible rate of conversion to open that is mainly related to some difficulty factors, as obesity. The aim of this study is to analyze the preoperative factors associated with conversion in obese patients with MIDP. METHODS: In this multicenter study, all obese patients who underwent MIDP at 18 international expert centers were included. The preoperative factors associated with conversion to open surgery were analyzed. RESULTS: Out of 436 patients, 91 (20.9%) underwent conversion to open, presenting higher blood loss, longer operative time and similar rate of major complications. Twenty (22%) patients received emergent conversion. At univariate analysis, the type of approach, radiological invasion of adjacent organs, preoperative enlarged lymphnodes and ASA ≥ III were significantly associated with conversion to open. At multivariate analysis, robotic approach showed a significantly lower conversion rate (14.6 % vs 27.3%, OR = 2.380, p = 0.001). ASA ≥ III (OR = 2.391, p = 0.002) and preoperative enlarged lymphnodes (OR = 3.836, p = 0.003) were also independently associated with conversion. CONCLUSION: Conversion rate is significantly lower in patients undergoing robotic approach. Radiological enlarged lymphnodes and ASA ≥ III are also associated with conversion to open. Conversion is associated with poorer perioperative outcomes, especially in case of intraoperative hemorrhage.