Predicting futility of upfront surgery in perihilar cholangiocarcinoma: Machine learning analytics model to optimize treatment allocation.

BACKGROUND: While resection remains the only curative option for perihilar cholangiocarcinoma, it is well known that such surgery is associated with a high risk of morbidity and mortality. Nevertheless, beyond facing life-threatening complications, patients may also develop early disease recurrence, defining a "futile" outcome in perihilar cholangiocarcinoma surgery. The aim of this study is to predict the high-risk category (futile group) where surgical benefits are reversed and alternative treatments may be considered. METHODS: The study cohort included prospectively maintained data from 27 Western tertiary referral centers: the population was divided into a development and a validation cohort. The Framingham Heart Study methodology was used to develop a preoperative scoring system predicting the "futile" outcome. RESULTS: A total of 2271 cases were analyzed: among them, 309 were classified within the "futile group" (13.6%). American Society of Anesthesiology (ASA) score ≥ 3 (OR 1.60; p = 0.005), bilirubin at diagnosis ≥50 mmol/L (OR 1.50; p = 0.025), Ca 19-9 ≥ 100 U/mL (OR 1.73; p = 0.013), preoperative cholangitis (OR 1.75; p = 0.002), portal vein involvement (OR 1.61; p = 0.020), tumor diameter ≥3 cm (OR 1.76; p < 0.001), and left-sided resection (OR 2.00; p < 0.001) were identified as independent predictors of futility. The point system developed, defined three (ie, low, intermediate, and high) risk classes, which showed good accuracy (AUC 0.755) when tested on the validation cohort. CONCLUSIONS: The possibility to accurately estimate, through a point system, the risk of severe postoperative morbidity and early recurrence, could be helpful in defining the best management strategy (surgery vs. nonsurgical treatments) according to preoperative features.

Lymphatic Invasion of Plakoglobin-Dependent Tumor Cell Clusters Drives Formation of Polyclonal Lung Metastases in Colon Cancer.

BACKGROUND & AIMS: Patients with colon cancer with liver metastases may be cured with surgery, but the presence of additional lung metastases often precludes curative treatment. Little is known about the processes driving lung metastasis. This study aimed to elucidate the mechanisms governing lung vs liver metastasis formation. METHODS: Patient-derived organoid (PDO) cultures were established from colon tumors with distinct patterns of metastasis. Mouse models recapitulating metastatic organotropism were created by implanting PDOs into the cecum wall. Optical barcoding was applied to trace the origin and clonal composition of liver and lung metastases. RNA sequencing and immunohistochemistry were used to identify candidate determinants of metastatic organotropism. Genetic, pharmacologic, in vitro, and in vivo modeling strategies identified essential steps in lung metastasis formation. Validation was performed by analyzing patient-derived tissues. RESULTS: Cecum transplantation of 3 distinct PDOs yielded models with distinct metastatic organotropism: liver only, lung only, and liver and lung. Liver metastases were seeded by single cells derived from select clones. Lung metastases were seeded by polyclonal clusters of tumor cells entering the lymphatic vasculature with very limited clonal selection. Lung-specific metastasis was associated with high expression of desmosome markers, including plakoglobin. Plakoglobin deletion abrogated tumor cell cluster formation, lymphatic invasion, and lung metastasis formation. Pharmacologic inhibition of lymphangiogenesis attenuated lung metastasis formation. Primary human colon, rectum, esophagus, and stomach tumors with lung metastases had a higher N-stage and more plakoglobin-expressing intra-lymphatic tumor cell clusters than those without lung metastases. CONCLUSIONS: Lung and liver metastasis formation are fundamentally distinct processes with different evolutionary bottlenecks, seeding entities, and anatomic routing. Polyclonal lung metastases originate from plakoglobin-dependent tumor cell clusters entering the lymphatic vasculature at the primary tumor site.

Robotic Versus Open Hepatic Arterial Infusion Pump Placement for Unresectable Intrahepatic Cholangiocarcinoma.

BACKGROUND: Hepatic arterial infusion pump (HAIP) chemotherapy is an effective treatment for patients with unresectable intrahepatic cholangiocarcinoma (iCCA). HAIP chemotherapy requires a catheter inserted in the gastroduodenal artery and a subcutaneous pump. The catheter can be placed using an open or robotic approach. OBJECTIVE: This study aimed to compare perioperative outcomes of robotic versus open HAIP placement in patients with unresectable iCCA. METHODS: We analyzed patients with unresectable iCCA included in the PUMP-II trial from January 2020 to September 2022 undergoing robotic or open HAIP placement at Amsterdam UMC, Erasmus MC, and UMC Utrecht. The primary outcome was time to functional recovery (TTFR). RESULTS: In total, 22 robotic and 28 open HAIP placements were performed. The median TTFR was 2 days after robotic placement versus 5 days after open HAIP placement (p < 0.001). One patient (4.5%) in the robotic group underwent a conversion to open because of a large bulky tumor leaning on the hilum immobilizing the liver. Postoperative complications were similar-36% (8/22) after robotic placement versus 39% (11/28) after open placement (p = 1.000). The median length of hospital stay was shorter in the robotic group-3 versus 5 days (p < 0.001). All 22 robotic patients initiated HAIP chemotherapy post-surgery, i.e. 93% (26/28) in the open group (p = 0.497). The median time to start HAIP chemotherapy was 14 versus 18 days (p = 0.153). CONCLUSION: Robotic HAIP placement in patients with unresectable iCCA is a safe and effective procedure and is associated with a significantly shorter TTFR and hospital stay than open HAIP placement.

Higher Postoperative Mortality and Inferior Survival After Right-Sided Liver Resection for Perihilar Cholangiocarcinoma: Left-Sided Resection is Preferred When Possible.

BACKGROUND: A right- or left-sided liver resection can be considered in about half of patients with perihilar cholangiocarcinoma (pCCA), depending on tumor location and vascular involvement. This study compared postoperative mortality and long-term survival of right- versus left-sided liver resections for pCCA. METHODS: Patients who underwent major liver resection for pCCA at 25 Western centers were stratified according to the type of hepatectomy-left, extended left, right, and extended right. The primary outcomes were 90-day mortality and overall survival (OS). RESULTS: Between 2000 and 2022, 1701 patients underwent major liver resection for pCCA. The 90-day mortality was 9% after left-sided and 18% after right-sided liver resection (p < 0.001). The 90-day mortality rates were 8% (44/540) after left, 11% (29/276) after extended left, 17% (51/309) after right, and 19% (108/576) after extended right hepatectomy (p < 0.001). Median OS was 30 months (95% confidence interval [CI] 27-34) after left and 23 months (95% CI 20-25) after right liver resection (p < 0.001), and 33 months (95% CI 28-38), 27 months (95% CI 23-32), 25 months (95% CI 21-30), and 21 months (95% CI 18-24) after left, extended left, right, and extended right hepatectomy, respectively (p < 0.001). A left-sided resection was an independent favorable prognostic factor for both 90-day mortality and OS compared with right-sided resection, with similar results after excluding 90-day fatalities. CONCLUSIONS: A left or extended left hepatectomy is associated with a lower 90-day mortality and superior OS compared with an (extended) right hepatectomy for pCCA. When both a left and right liver resection are feasible, a left-sided liver resection is preferred.

Hospital variation and outcomes after repeat hepatic resection for colorectal liver metastases: a nationwide cohort study.

BACKGROUND: Approximately 70% of patients with colorectal liver metastases (CRLM) experiences intrahepatic recurrence after initial liver resection. This study assessed outcomes and hospital variation in repeat liver resections (R-LR). METHODS: This population-based study included all patients who underwent liver resection for CRLM between 2014 and 2022 in the Netherlands. Overall survival (OS) was collected for patients operated on between 2014 and 2018 by linkage to the insurance database. RESULTS: Data of 7479 liver resections (1391 (18.6%) repeat and 6088 (81.4%) primary) were analysed. Major morbidity and mortality were not different. Factors associated with major morbidity included ASA 3+, major liver resection, extrahepatic disease, and open surgery. Five-year OS after repeat versus primary liver resection was 42.3% versus 44.8%, P = 0.37. Factors associated with worse OS included largest CRLM >5 cm (aHR 1.58, 95% CI: 1.07-2.34, P = 0.023), >3 CRLM (aHR 1.33, 95% CI: 1.00-1.75, P = 0.046), extrahepatic disease (aHR 1.60, 95% CI: 1.25-2.04, P = 0.001), positive tumour margins (aHR 1.42, 95% CI: 1.09-1.85, P = 0.009). Significant hospital variation in performance of R-LR was observed, median 18.9% (8.2% to 33.3%). CONCLUSION: Significant hospital variation was observed in performance of R-LR in the Netherlands reflecting different treatment decisions upon recurrence. On a population-based level R-LR leads to satisfactory survival.

Extrahepatic perfusion and incomplete hepatic perfusion after hepatic arterial infusion pump implantation: incidence and clinical implications.

INTRODUCTION: This study investigates the incidence of extrahepatic perfusion and incomplete hepatic perfusion at intraoperative methylene blue testing and on postoperative nuclear imaging in patients undergoing hepatic arterial infusion pump (HAIP) chemotherapy. METHODS: The first 150 consecutive patients who underwent pump implantation in the Netherlands were included. All patients underwent surgical pump implantation with the catheter in the gastroduodenal artery. All patients underwent intraoperative methylene blue testing and postoperative nuclear imaging (99mTc-Macroaggregated albumin SPECT/CT) to determine perfusion via the pump. RESULTS: Patients were included between January-2018 and December-2021 across eight centers. During methylene blue testing, 29.3% had extrahepatic perfusion, all successfully managed intraoperatively. On nuclear imaging, no clinically relevant extrahepatic perfusion was detected (0%, 95%CI: 0.0-2.5%). During methylene blue testing, 2.0% had unresolved incomplete hepatic perfusion. On postoperative nuclear imaging, 8.1% had incomplete hepatic perfusion, leading to embolization in only 1.3%. CONCLUSION: Methylene blue testing during pump placement for intra-arterial chemotherapy identified extrahepatic perfusion in 29.3% of patients, but could be resolved intraoperatively in all patients. Postoperative nuclear imaging found no clinically relevant extrahepatic perfusion and led to embolization in only 1.3% of patients. The role of routine nuclear imaging after HAIP implantation should be studied in a larger cohort.

Implementation and Outcome of Robotic Liver Surgery in the Netherlands: A Nationwide Analysis.

OBJECTIVE: To determine the nationwide implementation and surgical outcome of minor and major robotic liver surgery (RLS) and assess the first phase of implementation of RLS during the learning curve. BACKGROUND: RLS may be a valuable alternative to laparoscopic liver surgery. Nationwide population-based studies with data on implementation and outcome of RLS are lacking. METHODS: Multicenter retrospective cohort study including consecutive patients who underwent RLS for all indications in 9 Dutch centers (August 2014-March 2021). Data on all liver resections were obtained from the mandatory nationwide Dutch Hepato Biliary Audit (DHBA) including data from all 27 centers for liver surgery in the Netherlands. Outcomes were stratified for minor, technically major, and anatomically major RLS. Learning curve effect was assessed using cumulative sum analysis for blood loss. RESULTS: Of 9437 liver resections, 400 were RLS (4.2%) procedures including 207 minor (52.2%), 141 technically major (35.3%), and 52 anatomically major (13%). The nationwide use of RLS increased from 0.2% in 2014 to 11.9% in 2020. The proportion of RLS among all minimally invasive liver resections increased from 2% to 28%. Median blood loss was 150 mL (interquartile range 50-350 mL] and the conversion rate 6.3% (n=25). The rate of Clavien-Dindo grade ≥III complications was 7.0% (n=27), median length of hospital stay 4 days (interquartile range 2-5) and 30-day/in-hospital mortality 0.8% (n=3). The R0 resection rate was 83.2% (n=263). Cumulative sum analysis for blood loss found a learning curve of at least 33 major RLS procedures. CONCLUSIONS: The nationwide use of RLS in the Netherlands has increased rapidly with currently one-tenth of all liver resections and one-fourth of all minimally invasive liver resections being performed robotically. Although surgical outcomes of RLS in selected patient seem favorable, future prospective studies should determine its added value.

The Feasibility, Proficiency, and Mastery Learning Curves in 635 Robotic Pancreatoduodenectomies Following a Multicenter Training Program: "Standing on the Shoulders of Giants".

OBJECTIVE: To assess the feasibility, proficiency, and mastery learning curves for robotic pancreatoduodenectomy (RPD) in "second-generation" RPD centers following a multicenter training program adhering to the IDEAL framework. BACKGROUND: The long learning curves for RPD reported from "pioneering" expert centers may discourage centers interested in starting an RPD program. However, the feasibility, proficiency, and mastery learning curves may be shorter in "second-generation" centers that participated in dedicated RPD training programs, although data are lacking. We report on the learning curves for RPD in "second-generation" centers trained in a dedicated nationwide program. METHODS: Post hoc analysis of all consecutive patients undergoing RPD in 7 centers that participated in the LAELAPS-3 training program, each with a minimum annual volume of 50 pancreatoduodenectomies, using the mandatory Dutch Pancreatic Cancer Audit (March 2016-December 2021). Cumulative sum analysis determined cutoffs for the 3 learning curves: operative time for the feasibility (1) risk-adjusted major complication (Clavien-Dindo grade ≥III) for the proficiency, (2) and textbook outcome for the mastery, (3) learning curve. Outcomes before and after the cutoffs were compared for the proficiency and mastery learning curves. A survey was used to assess changes in practice and the most valued "lessons learned." RESULTS: Overall, 635 RPD were performed by 17 trained surgeons, with a conversion rate of 6.6% (n=42). The median annual volume of RPD per center was 22.5±6.8. From 2016 to 2021, the nationwide annual use of RPD increased from 0% to 23% whereas the use of laparoscopic pancreatoduodenectomy decreased from 15% to 0%. The rate of major complications was 36.9% (n=234), surgical site infection 6.3% (n=40), postoperative pancreatic fistula (grade B/C) 26.9% (n=171), and 30-day/in-hospital mortality 3.5% (n=22). Cutoffs for the feasibility, proficiency, and mastery learning curves were reached at 15, 62, and 84 RPD. Major morbidity and 30-day/in-hospital mortality did not differ significantly before and after the cutoffs for the proficiency and mastery learning curves. Previous experience in laparoscopic pancreatoduodenectomy shortened the feasibility (-12 RPDs, -44%), proficiency (-32 RPDs, -34%), and mastery phase learning curve (-34 RPDs, -23%), but did not improve clinical outcome. CONCLUSIONS: The feasibility, proficiency, and mastery learning curves for RPD at 15, 62, and 84 procedures in "second-generation" centers after a multicenter training program were considerably shorter than previously reported from "pioneering" expert centers. The learning curve cutoffs and prior laparoscopic experience did not impact major morbidity and mortality. These findings demonstrate the safety and value of a nationwide training program for RPD in centers with sufficient volume.

Novel Benchmark Values for Open Major Anatomic Liver Resection in Non-cirrhotic Patients: A Multicentric Study of 44 International Expert Centers.

OBJECTIVE: This study aims at establishing benchmark values for best achievable outcomes following open major anatomic hepatectomy for liver tumors of all dignities. BACKGROUND: Outcomes after open major hepatectomies vary widely lacking reference values for comparisons among centers, indications, types of resections, and minimally invasive procedures. METHODS: A standard benchmark methodology was used covering consecutive patients, who underwent open major anatomic hepatectomy from 44 high-volume liver centers from 5 continents over a 5-year period (2016-2020). Benchmark cases were low-risk non-cirrhotic patients without significant comorbidities treated in high-volume centers (≥30 major liver resections/year). Benchmark values were set at the 75th percentile of median values of all centers. Minimum follow-up period was 1 year in each patient. RESULTS: Of 8044 patients, 2908 (36%) qualified as benchmark (low-risk) cases. Benchmark cutoffs for all indications include R0 resection ≥78%; liver failure (grade B/C) ≤10%; bile leak (grade B/C) ≤18%; complications ≥grade 3 and CCI ® ≤46% and ≤9 at 3 months, respectively. Benchmark values differed significantly between malignant and benign conditions so that reference values must be adjusted accordingly. Extended right hepatectomy (H1, 4-8 or H4-8) disclosed a higher cutoff for liver failure, while extended left (H1-5,8 or H2-5,8) were associated with higher cutoffs for bile leaks, but had superior oncologic outcomes, when compared to formal left hepatectomy (H1-4 or H2-4). The minimal follow-up for a conclusive outcome evaluation following open anatomic major resection must be 3 months. CONCLUSION: These new benchmark cutoffs for open major hepatectomy provide a powerful tool to convincingly evaluate other approaches including parenchymal-sparing procedures, laparoscopic/robotic approaches, and alternative treatments, such as ablation therapy, irradiation, or novel chemotherapy regimens.

Algorithm-based care versus usual care for the early recognition and management of complications after pancreatic resection in the Netherlands: an open-label, nationwide, stepped-wedge cluster-randomised trial.

BACKGROUND: Early recognition and management of postoperative complications, before they become clinically relevant, can improve postoperative outcomes for patients, especially for high-risk procedures such as pancreatic resection. METHODS: We did an open-label, nationwide, stepped-wedge cluster-randomised trial that included all patients having pancreatic resection during a 22-month period in the Netherlands. In this trial design, all 17 centres that did pancreatic surgery were randomly allocated for the timing of the crossover from usual care (the control group) to treatment given in accordance with a multimodal, multidisciplinary algorithm for the early recognition and minimally invasive management of postoperative complications (the intervention group). Randomisation was done by an independent statistician using a computer-generated scheme, stratified to ensure that low-medium-volume centres alternated with high-volume centres. Patients and investigators were not masked to treatment. A smartphone app was designed that incorporated the algorithm and included the daily evaluation of clinical and biochemical markers. The algorithm determined when to do abdominal CT, radiological drainage, start antibiotic treatment, and remove abdominal drains. After crossover, clinicians were trained in how to use the algorithm during a 4-week wash-in period; analyses comparing outcomes between the control group and the intervention group included all patients other than those having pancreatic resection during this wash-in period. The primary outcome was a composite of bleeding that required invasive intervention, organ failure, and 90-day mortality, and was assessed by a masked adjudication committee. This trial was registered in the Netherlands Trial Register, NL6671. FINDINGS: From Jan 8, 2018, to Nov 9, 2019, all 1805 patients who had pancreatic resection in the Netherlands were eligible for and included in this study. 57 patients who underwent resection during the wash-in phase were excluded from the primary analysis. 1748 patients (885 receiving usual care and 863 receiving algorithm-centred care) were included. The primary outcome occurred in fewer patients in the algorithm-centred care group than in the usual care group (73 [8%] of 863 patients vs 124 [14%] of 885 patients; adjusted risk ratio [RR] 0·48, 95% CI 0·38-0·61; p<0·0001). Among patients treated according to the algorithm, compared with patients who received usual care there was a decrease in bleeding that required intervention (47 [5%] patients vs 51 [6%] patients; RR 0·65, 0·42-0·99; p=0·046), organ failure (39 [5%] patients vs 92 [10%] patients; 0·35, 0·20-0·60; p=0·0001), and 90-day mortality (23 [3%] patients vs 44 [5%] patients; 0·42, 0·19-0·92; p=0·029). INTERPRETATION: The algorithm for the early recognition and minimally invasive management of complications after pancreatic resection considerably improved clinical outcomes compared with usual care. This difference included an approximate 50% reduction in mortality at 90 days. FUNDING: The Dutch Cancer Society and UMC Utrecht.

Survival of Patients with Deficient Mismatch Repair Versus Proficient Mismatch Repair Metastatic Colorectal Cancer Receiving Curative-Intent Local Treatment of Metastases in a Nationwide Cohort.

BACKGROUND: It is unclear whether curative-intent local therapy of metastases is of similar benefit for the biological distinct subgroup of patients with deficient mismatch repair (dMMR) metastatic colorectal cancer (mCRC) compared with proficient mismatch repair (pMMR) mCRC. PATIENTS AND METHODS: In this nationwide study, recurrence-free (RFS) and overall survival (OS) were analyzed in patients with dMMR versus pMMR mCRC who underwent curative-intent local treatment of metastases between 2015 and 2018. Subgroup analyses were performed for resection of colorectal liver metastases (CRLM) and cytoreductive surgery ± hyperthermic intraperitoneal chemotherapy (CRS ± HIPEC). Multivariable regression was conducted. RESULTS: Median RFS was 11.1 months [95% confidence interval (CI) 8.5-41.1 months] for patients with dMMR tumors compared with 8.9 months (95% CI 8.1-9.8 months) for pMMR tumors. Two-year RFS was higher in patients with dMMR versus pMMR (43% vs. 21%). Results were similar within subgroups of local treatment (CRLM and CRS ± HIPEC). Characteristics differed significantly between patients with dMMR and pMMR mCRC; however, multivariable analysis continued to demonstrate dMMR as independent factor for improved RFS [hazard ratio (HR): 0.57, 95% CI 0.38-0.87]. Median OS was 33.3 months for dMMR mCRC compared with 43.5 months for pMMR mCRC, mainly due to poor survival of patients with dMMR in cases of recurrence in the preimmunotherapy era. CONCLUSION: Patients with dMMR eligible for curative-intent local treatment of metastases showed a comparable to more favorable RFS compared with patients with pMMR, with a clinically relevant proportion of patients remaining free of recurrence. This supports local treatment as a valuable treatment option in patients with dMMR mCRC and can aid in shared decision-making regarding upfront local therapy versus immunotherapy.

Predicting early extrahepatic recurrence after local treatment of colorectal liver metastases.

BACKGROUND: Patients who develop early extrahepatic recurrence (EHR) may not benefit from local treatment of colorectal liver metastases (CRLMs). This study aimed to develop a prediction model for early EHR after local treatment of CRLMs using a national data set. METHODS: A Cox regression prediction model for EHR was developed and validated internally using data on patients who had local treatment for CRLMs with curative intent. Performance assessment included calibration, discrimination, net benefit, and generalizability by internal-external cross-validation. The prognostic relevance of early EHR (within 6 months) was evaluated by landmark analysis. RESULTS: During a median follow-up of 35 months, 557 of the 1077 patients had EHR and 249 died. Median overall survival was 19.5 (95 per cent c.i. 15.6 to 23.0) months in patients with early EHR after CRLM treatment, compared with not reached (45.3 months to not reached) in patients without an early EHR. The EHR prediction model included side and stage of the primary tumour, RAS/BRAFV600E mutational status, and number and size of CRLMs. The range of 6-month EHR predictions was 5.9-56.0 (i.q.r. 12.9-22.0) per cent. The model demonstrated good calibration and discrimination. The C-index through 6 and 12 months was 0.663 (95 per cent c.i. 0.624 to 0.702) and 0.661 (0.632 to 0.689) respectively. The observed 6-month EHR risk was 6.5 per cent for patients in the lowest quartile of predicted risk compared with 32.0 per cent in the highest quartile. CONCLUSION: Early EHR after local treatment of CRLMs can be predicted.

Dose finding study for unilobar radioembolization using holmium-166 microspheres to improve resectability in patients with HCC: the RALLY protocol.

BACKGROUND: High dose unilobar radioembolization (also termed 'radiation lobectomy')-the transarterial unilobar infusion of radioactive microspheres as a means of controlling tumour growth while concomitantly inducing future liver remnant hypertrophy-has recently gained interest as induction strategy for surgical resection. Prospective studies on the safety and efficacy of the unilobar radioembolization-surgery treatment algorithm are lacking. The RALLY study aims to assess the safety and toxicity profile of holmium-166 unilobar radioembolization in patients with hepatocellular carcinoma ineligible for surgery due to insufficiency of the future liver remnant. METHODS: The RALLY study is a multicenter, interventional, non-randomized, open-label, non-comparative safety study. Patients with hepatocellular carcinoma who are considered ineligible for surgery due to insufficiency of the future liver remnant (< 2.7%/min/m2 on hepatobiliary iminodiacetic acid scan will be included. A classical 3 + 3 dose escalation model will be used, enrolling three to six patients in each cohort. The primary objective is to determine the maximum tolerated treated non-tumourous liver-absorbed dose (cohorts of 50, 60, 70 and 80 Gy). Secondary objectives are to evaluate dose-response relationships, to establish the safety and feasibility of surgical resection following unilobar radioembolization, to assess quality of life, and to generate a biobank. DISCUSSION: This will be the first clinical study to assess the unilobar radioembolization-surgery treatment algorithm and may serve as a stepping stone towards its implementation in routine clinical practice. TRIAL REGISTRATION: Netherlands Trial Register NL8902 , registered on 2020-09-15.

Practice variation and outcomes of minimally invasive minor liver resections in patients with colorectal liver metastases: a population-based study.

INTRODUCTION: In 2017, the Southampton guideline stated that minimally invasive liver resections (MILR) should considered standard practice for minor liver resections. This study aimed to assess recent implementation rates of minor MILR, factors associated with performing MILR, hospital variation, and outcomes in patients with colorectal liver metastases (CRLM). METHODS: This population-based study included all patients who underwent minor liver resection for CRLM in the Netherlands between 2014 and 2021. Factors associated with MILR and nationwide hospital variation were assessed using multilevel multivariable logistic regression. Propensity-score matching (PSM) was applied to compare outcomes between minor MILR and minor open liver resections. Overall survival (OS) was assessed with Kaplan-Meier analysis on patients operated until 2018. RESULTS: Of 4,488 patients included, 1,695 (37.8%) underwent MILR. PSM resulted in 1,338 patients in each group. Implementation of MILR increased to 51.2% in 2021. Factors associated with not performing MILR included treatment with preoperative chemotherapy (aOR 0.61 CI:0.50-0.75, p < 0.001), treatment in a tertiary referral hospital (aOR 0.57 CI:0.50-0.67, p < 0.001), and larger diameter and number of CRLM. Significant hospital variation was observed in use of MILR (7.5% to 93.0%). After case-mix correction, six hospitals performed fewer, and six hospitals performed more MILRs than expected. In the PSM cohort, MILR was associated with a decrease in blood loss (aOR 0.99 CI:0.99-0.99, p < 0.01), cardiac complications (aOR 0.29, CI:0.10-0.70, p = 0.009), IC admissions (aOR 0.66, CI:0.50-0.89, p = 0.005), and shorter hospital stay (aOR CI:0.94-0.99, p < 0.01). Five-year OS rates for MILR and OLR were 53.7% versus 48.6%, p = 0.21. CONCLUSION: Although uptake of MILR is increasing in the Netherlands, significant hospital variation remains. MILR benefits short-term outcomes, while overall survival is comparable to open liver surgery.

The diagnostic value of staging laparoscopy in gallbladder cancer: a nationwide cohort study.

BACKGROUND: Disseminated disease (DD) is often found at (re-)exploration in gallbladder cancer (GBC) patients. We aimed to assess the yield of staging laparoscopy (SL) and identify predictors for DD. METHODS: This retrospective study included patients from all Dutch academic centres with primary GBC (pGBC) and incidentally diagnosed GBC (iGBC) planned for (re-)resection. The yield of SL was determined. In iGBC, predictive factors for DD were assessed. RESULTS: In total, 290 patients were included. Of 183 included pGBC patients, 143 underwent laparotomy without SL, and 42 (29%) showed DD perioperatively. SL, conducted in 40 patients, identified DD in eight. DD was found in nine of 32 patients who underwent laparotomy after SL. Of 107 included iGBC patients, 100 underwent laparotomy without SL, and 19 showed DD perioperatively. SL, conducted in seven patients, identified DD in one. Cholecystitis (OR = 4.25; 95% CI 1.51-11.91) and primary R1/R2 resection (OR = 3.94; 95% CI 1.39-11.19) were independent predictive factors for DD. CONCLUSIONS: In pGBC patients, SL may identify DD in up to 20% of patients and should be part of standard management. In iGBC patients, SL is indicated after primary resection for cholecystitis and after initial R1/R2 resection due to the association of these factors with DD.

Colorectal liver metastases that survive radioembolization display features of aggressive tumor behavior.

BACKGROUND: Radiation lobectomy is a therapeutic approach that involves targeted radiation delivery to induce future liver remnant hypertrophy and tumor control. In patients with colorectal liver metastases, only 30-40% have complete tumor regression. The importance of tumor biology in treatment response remains elusive. METHODS: Patients with colorectal liver metastases who received radiation lobectomy were selected from surgical pathology files. Using a machine learning scoring protocol, pathological response was correlated to tumor absorbed dose and expression of markers of radioresistance Ki-67 (proliferation), CAIX (hypoxia), Olfm4 (cancer stem cells) and CD45 (leukocytes). RESULTS: No linear association was found between tumor dose and response (ρ < 0.1, P = 0.73 (90Y), P = 0.92 (166Ho)). Response did correlate with proliferation (ρ = 0.56, P = 0.012), and non-responsive lesions had large pools (>15%) of Olfm4 positive cancer stem cells (Fisher's exact test, P = 0.0037). Responding lesions (regression grade ≤2) were highly hypoxic compared to moderate and non-responding lesions (P = 0.011). Non-responsive lesions had more tumor-infiltrating leukocytes (3240 cells/mm2 versus 650 cells/mm2), although this difference was not significant (P = 0.08). CONCLUSION: The aggressive phenotype of a subset of surviving cancer cells emphasizes the importance of prompt resection after radiation lobectomy.

Outcomes of a Multicenter Training Program in Robotic Pancreatoduodenectomy (LAELAPS-3).

OBJECTIVE: To assess feasibility and safety of a multicenter training program in robotic pancreatoduodenectomy (RPD) adhering to the IDEAL framework for implementation of surgical innovation. BACKGROUND: Good results for RPD have been reported from single center studies. However, data on feasibility and safety of implementation through a multicenter training program in RPD are lacking. METHODS: A multicenter training program in RPD was designed together with the University of Pittsburgh Medical Center, including an online video bank, robot simulation exercises, biotissue drills, and on-site proctoring. Benchmark patients were based on the criteria of Clavien. Outcomes were collected prospectively (March 2016-October 2019). Cumulative sum analysis of operative time was performed to distinguish the first and second phase of the learning curve. Outcomes were compared between both phases of the learning curve. Trends in nationwide use of robotic and laparoscopic PD were assessed in the Dutch Pancreatic Cancer Audit. RESULTS: Overall, 275 RPD procedures were performed in seven centers by 15 trained surgeons. The recent benchmark criteria for low-risk PD were met by 125 (45.5%) patients. The conversion rate was 6.5% (n = 18) and median blood loss 250ml [interquartile range (IQR) 150-500]. The rate of Clavien-Dindo grade ≥III complications was 44.4% (n = 122), postoperative pancreatic fistula (grade B/C) rate 23.6% (n = 65), 90-day complication-related mortality 2.5% (n = 7) and 90-day cancer-related mortality 2.2.% (n = 6). Median postoperative hospital stay was 12 days (IQR 8-20). In the subgroup of patients with pancreatic cancer (n = 80), the major complication rate was 31.3% and POPF rate was 10%. Cumulative sum analysis for operative time found a learning curve inflection point at 22 RPDs (IQR 10-35) with similar rates of Clavien-Dindo grade ≥III complications in the first and second phase (43.4% vs 43.8%, P = 0.956, respectively). During the study period the nationwide use of laparoscopic PD reduced from 15% to 1%, whereas the use of RPD increased from 0% to 25%. CONCLUSIONS: This multicenter RPD training program in centers with sufficient surgical volume was found to be feasible without a negative impact of the learning curve on clinical outcomes.

Somatostatin analogues for the prevention of pancreatic fistula after open pancreatoduodenectomy: A nationwide analysis.

BACKGROUND: Somatostatin analogues (SA) are currently used to prevent postoperative pancreatic fistula (POPF) development. However, its use is controversial. This study investigated the effect of different SA protocols on the incidence of POPF after pancreatoduodenectomy in a nationwide population. METHODS: All patients undergoing elective open pancreatoduodenectomy were included from the Dutch Pancreatic Cancer Audit (2014-2017). Patients were divided into six groups: no SA, octreotide, lanreotide, pasireotide, octreotide only in high-risk (HR) patients and lanreotide only in HR patients. Primary endpoint was POPF grade B/C. The updated alternative Fistula Risk Score was used to compare POPF rates across various risk scenarios. RESULTS: 1992 patients were included. Overall POPF rate was 13.1%. Lanreotide (10.0%), octreotide-HR (9.4%) and no protocol (12.7%) POPF rates were lower compared to the other protocols (varying from 15.1 to 19.1%, p = 0.001) in crude analysis. Sub-analysis in patients with HR of POPF showed a significantly lower rate of POPF when treated with lanreotide (10.0%) compared to no protocol, octreotide and pasireotide protocol (21.6-26.9%, p = 0.006). Octreotide-HR and lanreotide-HR protocol POPF rates were comparable to lanreotide protocol, however not significantly different from the other protocols. Multivariable regression analysis demonstrated lanreotide protocol to be positively associated with a low odds-ratio (OR) for POPF (OR 0.387, 95% CI 0.180-0.834, p = 0.015). In-hospital mortality rates were not affected. CONCLUSION: Use of lanreotide in all patients undergoing pancreatoduodenectomy has a potential protective effect on POPF development. Protocols for HR patients only might be favorable too. However, future studies are warranted to confirm these findings.

Pan-European survey on the implementation of robotic and laparoscopic minimally invasive liver surgery.

BACKGROUND: Laparoscopic and robotic minimally invasive liver surgery (MILS) is gaining popularity. Recent data and views on the implementation of laparoscopic and robotic MILS throughout Europe are lacking. METHODS: An anonymous survey consisting of 46 questions was sent to all members of the European-African Hepato-Pancreato-Biliary Association. RESULTS: The survey was completed by 120 surgeons from 103 centers in 24 countries. Median annual center volume of liver resection was 100 [IQR 50-140]. The median annual volume of MILS per center was 30 [IQR 16-40]. For minor resections, laparoscopic MILS was used by 80 (67%) surgeons and robotic MILS by 35 (29%) surgeons. For major resections, laparoscopic MILS was used by 74 (62%) surgeons and robotic MILS by 33 (28%) surgeons. The majority of the surgeons stated that minimum annual volume of MILS per center should be around 21-30 procedures/year. Of the surgeons performing robotic surgery, 28 (70%) felt they missed specific equipment, such as a robotic-CUSA. Seventy (66%) surgeons provided a formal MILS training to residents and fellows. In 5 years' time, 106 (88%) surgeons felt that MILS would have superior value as compared to open liver surgery. CONCLUSION: In the participating European liver centers, MILS comprised about one third of all liver resections and is expected to increase further. Laparoscopic MILS is still twice as common as robotic MILS. Development of specific instruments for robotic liver parenchymal transection might further increase its adoption.

Short-term postoperative outcomes after liver resection in the elderly patient: a nationwide population-based study.

BACKGROUND: Liver resection is high-risk surgery in particular in elderly patients. The aim of this study was to explore postoperative outcomes after liver resection in elderly patients. METHODS: In this nationwide study, all patients who underwent liver resection for primary and secondary liver tumours in the Netherlands between 2014 and 2019 were included. Age groups were composed as younger than 70 (70-), between 70 and 80 (septuagenarians), and 80 years or older (octogenarians). Proportion of liver resections per age group and 30-day major morbidity and 30-day mortality were assessed. RESULTS: In total, 6587 patients were included of whom 4023 (58.9%) were younger than 70, 2135 (32.4%) were septuagenarians and 429 (6.5%) were octogenarians. The proportion of septuagenarians increased during the study period (aOR:1.06, CI:1.02-1.09, p < 0.001). Thirty-day major morbidity was higher in septuagenarians (11%) and octogenarians (12%) compared to younger patients (9%, p = 0.049). Thirty-day mortality was higher in septuagenarians (4%) and octogenarians (4%) compared to younger patients (2%, p < 0.001). Cardiopulmonary complications occurred more frequently with higher age, liver-specific complications did not. Higher age was associated with higher 30-day morbidity and 30-day mortality in multivariable logistic regression. CONCLUSION: Thirty-day major morbidity and 30-day mortality are higher after liver resection in elderly patients, attributed mainly to non-surgical cardiopulmonary complications.