Background Robotic surgery may improve surgical performance during minimally invasive pancreatoduodenectomy as compared to 3D- and 2D-laparoscopy but comparative studies are lacking. This study... Show moreBackground Robotic surgery may improve surgical performance during minimally invasive pancreatoduodenectomy as compared to 3D- and 2D-laparoscopy but comparative studies are lacking. This study assessed the impact of robotic surgery versus 3D- and 2D-laparoscopy on surgical performance and operative time using a standardized biotissue model for pancreatico- and hepatico-jejunostomy using pooled data from two randomized controlled crossover trials (RCTs). Methods Pooled analysis of data from two RCTs with 60 participants (36 surgeons, 24 residents) from 11 countries (December 2017-July 2019) was conducted. Each included participant completed two pancreatico- and two hepatico-jejunostomies in biotissue using 3D-robotic surgery, 3D-laparoscopy, or 2D-laparoscopy. Primary outcomes were the objective structured assessment of technical skills (OSATS: 12-60) rating, scored by observers blinded for 3D/2D and the operative time required to complete both anastomoses. Sensitivity analysis excluded participants with excess experience compared to others. Results A total of 220 anastomoses were completed (robotic 80, 3D-laparoscopy 70, 2D-laparoscopy 70). Participants in the robotic group had less surgical experience [median 1 (0-2) versus 6 years (4-12), p < 0.001], as compared to the laparoscopic group. Robotic surgery resulted in higher OSATS ratings (50, 43, 39 points, p = .021 and p < .001) and shorter operative time (56.5, 65.0, 81.5 min, p = .055 and p < .001), as compared to 3D- and 2D-laparoscopy, respectively, which remained in the sensitivity analysis. Conclusion In a pooled analysis of two RCTs in a biotissue model, robotic surgery resulted in better surgical performance scores and shorter operative time for biotissue pancreatic and biliary anastomoses, as compared to 3D- and 2D-laparoscopy. Show less
BACKGROUNDInfected necrotizing pancreatitis is a potentially lethal disease that is treated with the use of a step-up approach, with catheter drainage often delayed until the infected necrosis is... Show moreBACKGROUNDInfected necrotizing pancreatitis is a potentially lethal disease that is treated with the use of a step-up approach, with catheter drainage often delayed until the infected necrosis is encapsulated. Whether outcomes could be improved by earlier catheter drainage is unknown.METHODSWe conducted a multicenter, randomized superiority trial involving patients with infected necrotizing pancreatitis, in which we compared immediate drainage within 24 hours after randomization once infected necrosis was diagnosed with drainage that was postponed until the stage of walled-off necrosis was reached. The primary end point was the score on the Comprehensive Complication Index, which incorporates all complications over the course of 6 months of follow-up.RESULTSA total of 104 patients were randomly assigned to immediate drainage (55 patients) or postponed drainage (49 patients). The mean score on the Comprehensive Complication Index (scores range from 0 to 100, with higher scores indicating more severe complications) was 57 in the immediate-drainage group and 58 in the postponed-drainage group (mean difference, -1; 95% confidence interval [CI], -12 to 10; P=0.90). Mortality was 13% in the immediate-drainage group and 10% in the postponed-drainage group (relative risk, 1.25; 95% CI, 0.42 to 3.68). The mean number of interventions (catheter drainage and necrosectomy) was 4.4 in the immediate-drainage group and 2.6 in the postponed-drainage group (mean difference, 1.8; 95% CI, 0.6 to 3.0). In the postponed-drainage group, 19 patients (39%) were treated conservatively with antibiotics and did not require drainage; 17 of these patients survived. The incidence of adverse events was similar in the two groups.CONCLUSIONSThis trial did not show the superiority of immediate drainage over postponed drainage with regard to complications in patients with infected necrotizing pancreatitis. Patients randomly assigned to the postponed-drainage strategy received fewer invasive interventions. Show less
Introduction: Whereas neoadjuvant chemo(radio)therapy is increasingly used in pancreatic cancer, it is currently not recommended for other periampullary (non-pancreatic) cancers. This has important... Show moreIntroduction: Whereas neoadjuvant chemo(radio)therapy is increasingly used in pancreatic cancer, it is currently not recommended for other periampullary (non-pancreatic) cancers. This has important implications for the relevance of the preoperative diagnosis for pancreatoduodenectomy. This retrospective multicentre cohort study aimed to determine the frequency of clinically relevant misdiagnoses in patients undergoing pancreatoduodenectomy for pancreatic or other periampullary cancer. Methods: Data from all consecutive patients who underwent a pancreatoduodenectomy between 2014 and 2018 were obtained from the prospective Dutch Pancreatic Cancer Audit. The preoperative diagnosis as concluded by the multidisciplinary team (MDT) meeting was compared with the final postoperative diagnosis at pathology to determine the rate of clinically relevant misdiagnosis (defined as missed pancreatic cancer or incorrect diagnosis of pancreatic cancer). Results: In total, 1244 patients underwent pancreatoduodenectomy of whom 203 (16%) had a clinically relevant misdiagnosis preoperatively. Of all patients with a final diagnosis of pancreatic cancer, 13% (87/ 679) were preoperatively misdiagnosed as distal cholangiocarcinoma (n = 41, 6.0%), ampullary cancer (n = 27, 4.0%) duodenal cancer (n = 16, 2.4%), or other (n = 3, 0.4%). Of all patients with a final diagnosis of periampullary (non-pancreatic) cancer, 21% (116/565) were preoperatively incorrectly diagnosed as pancreatic cancer. Accuracy of preoperative diagnosis was 84% for pancreatic cancer, 71% for distal cholangiocarcinoma, 73% for ampullary cancer and 73% for duodenal cancer. A prediction model for the preoperative likelihood of pancreatic cancer (versus other periampullary cancer) prior to pancreatoduodenectomy demonstrated an AUC of 0.88. Discussion: This retrospective multicentre cohort study showed that 16% of patients have a clinically relevant misdiagnosis that could result in either missing the opportunity of neoadjuvant chemotherapy in patients with pancreatic cancer or inappropriate administration of neoadjuvant chemotherapy in patients with non-pancreatic periampullary cancer. A preoperative prediction model is available on www.pancreascalculator.com. (c) 2021 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Show less
Background: The aim of this study was to determine pancreatic surgery specific short- and long-term complications of pediatric, adolescent and young adult (PAYA) patients who underwent pancreatic... Show moreBackground: The aim of this study was to determine pancreatic surgery specific short- and long-term complications of pediatric, adolescent and young adult (PAYA) patients who underwent pancreatic resection, as compared to a comparator cohort of adults. Methods: A nationwide retrospective cohort study was performed in PAYA patients who underwent pancreatic resection between 2007 and 2016. PAYA was defined as all patients 40 years at time of surgery. Pancreatic surgery-specific complications were assessed according to international definitions and textbook outcome was determined. Results: A total of 230 patients were included in the PAYA cohort (112 distal pancreatectomies, 99 pancreatoduodenectomies), and 2526 patients in the comparator cohort. For pancreatoduodenectomy, severe morbidity (29.3% vs. 28.6%; P = 0.881), in-hospital mortality (1% vs. 4%; P = 0.179) and textbook outcome (62% vs. 58%; P = 0.572) were comparable between the PAYA and the comparator cohort. These outcomes were also similar for distal pancreatectomy. After pancreatoduodenectomy, new-onset diabetes mellitus (8% vs. 16%) and exocrine pancreatic insufficiency (27% vs. 73%) were lower in the PAYA cohort when compared to adult literature. Conclusion: Pancreatic surgery-specific complications were comparable with patients 40 years. Development of endocrine and exocrine insufficiency in PAYA patients who underwent pancreatoduodenectomy, however, was substantially lower compared to adult literature. Show less
Background: Based on excellent outcomes from high-volume centres, laparoscopic liver resection is increasingly being adopted into nationwide practice which typically includes low-medium volume... Show moreBackground: Based on excellent outcomes from high-volume centres, laparoscopic liver resection is increasingly being adopted into nationwide practice which typically includes low-medium volume centres. It is unknown how the use and outcome of laparoscopic liver resection compare between high-volume centres and low-medium volume centres. This study aimed to compare use and outcome of laparoscopic liver resection in three leading European high-volume centres and nationwide practice in the Netherlands.Method: An international, retrospective multicentre cohort study including data from three European high-volume centres (Oslo, Southampton and Milan) and all 20 centres in the Netherlands performing laparoscopic liver resection (low-medium volume practice) from January 2011 to December 2016. A high-volume centre is defined as a centre performing >50 laparoscopic liver resections per year. Patients were retrospectively stratified into low, moderate- and high-risk Southampton difficulty score groups.Results: A total of 2425 patients were included (1540 high-volume; 885 low-medium volume). The median annual proportion of laparoscopic liver resection was 42.9 per cent in high-volume centres and 7.2 per cent in low-medium volume centres. Patients in the high-volume centres had a lower conversion rate (7.4 versus 13.1 per cent; P<0.001) with less intraoperative incidents (9.3 versus 14.6 per cent; P=0.002) as compared to low-medium volume centres. Whereas postoperative morbidity and mortality rates were similar in the two groups, a lower reintervention rate (5.1 versus 7.2 per cent; P=0.034) and a shorter postoperative hospital stay (3 versus 5 days; P<0.001) were observed in the high-volume centres as compared to the low-medium volume centres. In each Southampton difficulty score group, the conversion rate was lower and hospital stay shorter in high-volume centres. The rate of intraoperative incidents did not differ in the low-risk group, whilst in the moderate-risk and high-risk groups this rate was lower in high-volume centres (absolute difference 6.7 and 14.2 per cent; all P<0.004).Conclusion: High-volume expert centres had a sixfold higher use of laparoscopic liver resection, less conversions, and shorter hospital stay, as compared to a nationwide low-medium volume practice. Stratification into Southampton difficulty score risk groups identified some differences but largely outcomes appeared better for high-volume centres in each risk group. Show less
Introduction: First, this study aimed to assess the prognostic value of different definitions for resection margin status on disease-free survival (DFS) and overall survival (OS) in pancreatic... Show moreIntroduction: First, this study aimed to assess the prognostic value of different definitions for resection margin status on disease-free survival (DFS) and overall survival (OS) in pancreatic ductal adenocarcinoma (PDAC). Second, preoperative predictors of direct margin involvement were identified.Materials and methods: This nationwide observational cohort study included all patients who underwent upfront PDAC resection (2014-2016), as registered in the prospective Dutch Pancreatic Cancer Audit. Patients were subdivided into three groups: R0 (>= 1 mm margin clearance), R1 (<1 mm margin clearance) or R1 (direct margin involvement). Survival was compared using multivariable Cox regression analysis. Logistic regression with baseline variables was performed to identify preoperative predictors of R1 (direct).Results: 595 patients with a median OS of 18 months (IQR 10-32 months) months were analysed. R0 (>= 1 mm) was achieved in 277 patients (47%), R1 (<1 mm) in 146 patients (24%) and R1 (direct) in 172 patients (29%). R1 (direct) was associated with a worse OS, as compared with both R0 (>= 1 mm) (hazard ratio (HR) 1.35 [95% and confidence interval (CI) 1.08-1.70); P < 0.01) and R1 (<1 mm) (HR 1.29 [95%CI 1.01-1.67]; P < 0.05). No OS difference was found between R0 (>= 1 mm) and R1 (<1 mm) (HR 1.05 [95% CI 0.82-1.34]; P = 0.71). Preoperative predictors associated with an increased risk of R1 (direct) included age, male sex, performance score 2-4, and venous or arterial tumour involvement.Conclusion: Resection margin clearance of <1 mm, but without direct margin involvement, does not affect survival, as compared with a margin clearance of >1 mm. Given that any vascular tumour involvement on preoperative imaging was associated with an increased risk of R1 (direct) resection with upfront surgery, neoadjuvant therapy might be considered in these patients. (C) 2020 Published by Elsevier Ltd. Show less
Background: Guidelines advise self-expanding metal stents (SEMS) over plastic stents in preoperative endoscopic biliary drainage (EBD) for malignant extrahepatic biliary obstruction. This study... Show moreBackground: Guidelines advise self-expanding metal stents (SEMS) over plastic stents in preoperative endoscopic biliary drainage (EBD) for malignant extrahepatic biliary obstruction. This study aims to assess nationwide practice and outcomes.Methods: Patients with pancreatic head and periampullary cancer who underwent EBD before pancreatoduodenectomy were included from the Dutch Pancreatic Cancer Audit (2017 & ndash;2018). Multi variable logistic and linear regression models were performed.Results: In total, 575/1056 patients (62.0%) underwent preoperative EBD: 246 SEMS (42.8%) and 329 plastic stents (57.2%). EBD-related complications were comparable between the groups (44/246 (17.9%) vs. 64/329 (19.5%), p = 0.607), including pancreatitis (22/246 (8.9%) vs. 25/329 (7.6%), p = 0.387). EBD-related cholangitis was reduced after SEMS placement (10/246 (4.1%) vs. 32/329 (9.7%), p = 0.043), which was confirmed in multivariable analysis (OR 0.36 95%CI 0.15 & ndash;0.87, p = 0.023). Major postoperative complications did not differ (58/246 (23.6%) vs. 90/329 (27.4%), p = 0.316), whereas postoperative pancreatic fistula (24/246 (9.8%) vs. 61/329 (18.5%), p = 0.004; OR 0.50 95%CI 0.27 & ndash;0.94, p = 0.031) and hospital stay (14.0 days vs. 17.4 days, p = 0.005; B 2.86 95%CI & minus;5.16 to & minus;0.57, p = 0.014) were less after SEMS placement.Conclusion: This study found that preoperative EBD frequently involved plastic stents. SEMS seemed associated with lower risks of cholangitis and less postoperative pancreatic fistula, but without an increased pancreatitis risk. Show less
Background: The aim of this survey was to gain insights in the current surgical management and pathological assessment of pancreatoduodenectomy with portal-superior mesenteric vein resection (VR)... Show moreBackground: The aim of this survey was to gain insights in the current surgical management and pathological assessment of pancreatoduodenectomy with portal-superior mesenteric vein resection (VR).Methods: A systematic literature search was performed to identify international expert surgeons (N = 150) and pathologists (N = 40) who published relevant studies between 2009 and 2019. These experts and Dutch surgeons (N = 17) and pathologists (N = 20) were approached to complete an online survey.Results: Overall, 76 (46%) surgeons and 37 (62%) pathologists completed the survey. Most surgeons (71%) estimated that preoperative imaging corresponded correctly with intraoperative findings of venous involvement in 50-75% of patients. An increased complication risk following VR was expected by 55% of surgeons, mainly after Type 4 (segmental resection-venous conduit anastomosis). Most surgeons (61%) preferred Type 3 (segmental resection-primary anastomosis). Most surgeons (75%) always perform the VR themselves. Standard postoperative imaging for patency control was performed by 54% of surgeons and 39% adjusted thromboprophylaxis following VR. Most pathologists (76%) always assessed tumor infiltration in the resected vein and only 54% of pathologists always assess the resection margins of the vein itself. Variation in assessment of tumor infiltration depth was observed.Conclusion: This international survey showed variation in the surgical management and pathological assessment of pancreatoduodenectomy with venous involvement. This highlights the lack of evidence and emphasizes the need for research on imaging modalities to improve patient selection for VR, surgical techniques, postoperative management and standardization of the pathological assessment. Show less
Background: Compliance with national guidelines on pancreatic cancer management could improve patient outcomes. Early compliance with the Dutch guideline was poor. The aim was to assess compliance... Show moreBackground: Compliance with national guidelines on pancreatic cancer management could improve patient outcomes. Early compliance with the Dutch guideline was poor. The aim was to assess compliance with this guideline during six years after publication.Materials and methods: Nationwide guideline compliance was investigated for three subsequent time periods (2012-2013 vs. 2014-2015 vs. 2016-2017) in patients with pancreatic cancer using five quality indicators in the Netherlands Cancer Registry: 1) discussion in multidisciplinary team meeting (MDT), 2) maximum 3-week interval from final MDT to start of treatment, 3) preoperative biliary drainage when bilirubin >250 mu mol/L, 4) use of adjuvant chemotherapy, and 5) chemotherapy for inoperable disease (non-metastatic and metastatic).Results: In total, 14 491 patients were included of whom 2290 (15.8%) underwent resection and 4561 (31.5%) received chemotherapy. Most quality indicators did not change over time: overall, 88.8% of patients treated with curative intent were discussed in a MDT, 42.7% were treated with curative intent within the 3-week interval, 62.7% with a resectable head tumor and bilirubin >250 mu mol/L underwent preoperative biliary drainage, 57.2% received chemotherapy after resection, and 36.6% with metastatic disease received chemotherapy. Only use of chemotherapy for non-metastatic, non-resected disease improved over time (23.4% vs. 25.6% vs. 29.7%).Conclusion: Nationwide compliance to five quality indicators for the guideline on pancreatic cancer management showed little to no improvement during six years after publication. Besides critical review of the current quality indicators, these outcomes may suggest that a nationwide implementation program is required to increase compliance to guideline recommendations. (C) 2020 IAP and EPC. Published by Elsevier B.V. All rights reserved. Show less
BackgroundPancreatic cancer has a very poor prognosis. Best practices for the use of chemotherapy, enzyme replacement therapy, and biliary drainage have been identified but their implementation in... Show moreBackgroundPancreatic cancer has a very poor prognosis. Best practices for the use of chemotherapy, enzyme replacement therapy, and biliary drainage have been identified but their implementation in daily clinical practice is often suboptimal. We hypothesized that a nationwide program to enhance implementation of these best practices in pancreatic cancer care would improve survival and quality of life.Methods/designPACAP-1 is a nationwide multicenter stepped-wedge cluster randomized controlled superiority trial. In a per-center stepwise and randomized manner, best practices in pancreatic cancer care regarding the use of (neo)adjuvant and palliative chemotherapy, pancreatic enzyme replacement therapy, and metal biliary stents are implemented in all 17 Dutch pancreatic centers and their regional referral networks during a 6-week initiation period. Per pancreatic center, one multidisciplinary team functions as reference for the other centers in the network. Key best practices were identified from the literature, 3 years of data from existing nationwide registries within the Dutch Pancreatic Cancer Project (PACAP), and national expert meetings. The best practices follow the Dutch guideline on pancreatic cancer and the current state of the literature, and can be executed within daily clinical practice. The implementation process includes monitoring, return visits, and provider feedback in combination with education and reminders. Patient outcomes and compliance are monitored within the PACAP registries. Primary outcome is 1-year overall survival (for all disease stages). Secondary outcomes include quality of life, 3- and 5-year overall survival, and guideline compliance. An improvement of 10% in 1-year overall survival is considered clinically relevant. A 25-month study duration was chosen, which provides 80% statistical power for a mortality reduction of 10.0% in the 17 pancreatic cancer centers, with a required sample size of 2142 patients, corresponding to a 6.6% mortality reduction and 4769 patients nationwide.DiscussionThe PACAP-1 trial is designed to evaluate whether a nationwide program for enhanced implementation of best practices in pancreatic cancer care can improve 1-year overall survival and quality of life.Trial registrationClinicalTrials.gov, NCT03513705. Trial opened for accrual on 22th May 2018. Show less
Background Conditional survival is the survival probability after already surviving a predefined time period. This may be informative during follow-up, especially when adjusted for tumor... Show moreBackground Conditional survival is the survival probability after already surviving a predefined time period. This may be informative during follow-up, especially when adjusted for tumor characteristics. Such prediction models for patients with resected pancreatic cancer are lacking and therefore conditional survival was assessed and a nomogram predicting 5-year survival at a predefined period after resection of pancreatic cancer was developed. Methods This population-based study included patients with resected pancreatic ductal adenocarcinoma from the Netherlands Cancer Registry (2005-2016). Conditional survival was calculated as the median, and the probability of surviving up to 8 years in patients who already survived 0-5 years after resection was calculated using the Kaplan-Meier method. A prediction model was constructed. Results Overall, 3082 patients were included, with a median age of 67 years. Median overall survival was 18 months (95% confidence interval 17-18 months), with a 5-year survival of 15%. The 1-year conditional survival (i.e. probability of surviving the next year) increased from 55 to 74 to 86% at 1, 3, and 5 years after surgery, respectively, while the median overall survival increased from 15 to 40 to 64 months at 1, 3, and 5 years after surgery, respectively. The prediction model demonstrated that the probability of achieving 5-year survival at 1 year after surgery varied from 1 to 58% depending on patient and tumor characteristics. Conclusions This population-based study showed that 1-year conditional survival was 55% 1 year after resection and 74% 3 years after resection in patients with pancreatic cancer. The prediction model is available via to inform patients and caregivers. Show less
Background: The relation between type of postoperative complication and not receiving chemotherapy after resection of pancreatic ductal adenocarcinoma (PDAC) is unclear. The aim was to investigate... Show moreBackground: The relation between type of postoperative complication and not receiving chemotherapy after resection of pancreatic ductal adenocarcinoma (PDAC) is unclear. The aim was to investigate which patient factors and postoperative complications were associated with not receiving adjuvant chemotherapy.Methods: Patients who underwent resection (2014-2017) for PDAC were identified from the nationwide mandatory Dutch Pancreatic Cancer Audit. The association between patient-, tumor-, center-, treatment characteristics, and the risk of not receiving adjuvant chemotherapy was analyzed with multivariable logistic regression.Results: Overall, of 1306 patients, 24% (n = 312) developed postoperative Clavien Dindo >3 complications. In-hospital mortality was 3.5% (n = 46). Some 433 patients (33%) did not receive adjuvant chemotherapy. Independent predictors (all p < 0.050) for not receiving adjuvant chemotherapy were older age (odds ratio (OR) 0.96), higher ECOG performance status (OR 0.57), postoperative complications (OR 0.32), especially grade B/C pancreatic fistula (OR 0.51) and post-pancreatectomy hemorrhage (OR 0.36), poor tumor differentiation grade (OR 0.62), and annual center volume of <40 pancreatoduodenectomies (OR 0.51).Conclusions: This study demonstrated that a third of patients do not receive chemotherapy after resection of PDAC. Next to higher age, worse performance status and lower annual surgical volume, this is mostly related to surgical complications, especially postoperative pancreatic fistula and postpancreatectomy hemorrhage. Show less
Roessel, S. van; Mackay, T.M.; Dieren, S. van; Schelling, G.P. van der; Nieuwenhutjs, V.B.; Bosscha, K.; ... ; Dutch Pancreatic Canc Grp 2020
Background: Textbook outcome (TO) is a multidimensional measure for quality assurance, reflecting the "ideal" surgical outcome. Methods: Post-hoc analysis of patients who underwent... Show moreBackground: Textbook outcome (TO) is a multidimensional measure for quality assurance, reflecting the "ideal" surgical outcome. Methods: Post-hoc analysis of patients who underwent pancreatoduodenectomy (PD) or distal pancreatectomy (DP) for all indications between 2014 and 2017, queried from the nationwide prospective Dutch Pancreatic Cancer Audit. An international survey was conducted among 24 experts from 10 countries to reach consensus on the requirements for TO in pancreatic surgery. Univariable and multivariable logistic regression was performed to identify TO predictors. Between-hospital variation in TO rates was compared using observed-versus-expected rates. Results: Based on the survey (92% response rate), TO was defined by the absence of postoperative pancreatic fistula, bile leak, postpancreatectomy hemorrhage (all ISGPS grade B/C), severe complications (Clavien-Dindo >= III), readmission, and in-hospital mortality. Overall, 3341 patients were included (2633 (79%) PD and 708 (21%) DP) of whom 60.3% achieved TO; 58.3% for PD and 67.4% for DP. On multivariable analysis, ASA class 3 predicted a worse TO rate after PD (ASA 3 OR 0.59 [0.44-0.80]), whereas a dilated pancreatic duct (>3 mm) and pancreatic ductal adenocarcinoma (PDAC) were associated with a better TO rate (OR 2.22 [2.05-3.57] and OR 1.36 [1.14-1.63], respectively). For DP, female sex and the absence of neoadjuvant therapy predicted better TO rates (OR 1.38 [1.01-1.90] and OR 2.53 [1.20-5.31], respectively). When comparing institutions, the observed-versus-expected rate for achieving TO varied from 0.71 to 1.46 per hospital after casemix-adjustment. Conclusions: TO is a novel quality measure in pancreatic surgery. TO varies considerably between pancreatic centers, demonstrating the potential benefit of quality assurance programs. Show less
Background: While most of the evidence on minimally invasive liver surgery (MILS) is derived from expert centers, nationwide outcomes remain underreported. This study aimed to evaluate the... Show moreBackground: While most of the evidence on minimally invasive liver surgery (MILS) is derived from expert centers, nationwide outcomes remain underreported. This study aimed to evaluate the implementation and outcome of MILS on a nationwide scale.Methods: Electronic patient files were reviewed in all Dutch liver surgery centers and all patients undergoing MILS between 2011 and 2016 were selected. Operative outcomes were stratified based on extent of the resection and annual MILS volume.Results: Overall, 6951 liver resections were included, with a median annual volume of 50 resections per center. The overall use of MILS was 13% (n = 916), which varied from 3% to 36% (P < 0.001) between centers. The nationwide use of MILS increased from 6% in 2011 to 23% in 2016 (P < 0.001). Outcomes of minor MILS were comparable with international studies (conversion 0- 13%, mortality <1%). In centers which performed >= 20 MILS annually, major MILS was associated with less conversions (14 (11%) versus 41 (30%), P < 0.001), shorter operating time (184 (117- 239) versus 200 (139-308) minutes, P = 0.010), and less overall complications (37 (30%) versus 58 (42%), P = 0.040).Conclusion: The nationwide use of MILS is increasing, although large variation remains between centers. Outcomes of major MILS are better in centers with higher volumes. Show less
