Preoperative chemoradiotherapy but not chemotherapy is associated with reduced risk of postoperative pancreatic fistula after pancreatoduodenectomy for pancreatic ductal adenocarcinoma: a nationwide analysis

BACKGROUND

Postoperative pancreatic fistula remains the leading cause of significant morbidity after pancreatoduodenectomy for pancreatic ductal adenocarcinoma. Preoperative chemoradiotherapy has been described to reduce the risk of postoperative pancreatic fistula, but randomized trials on neoadjuvant treatment in pancreatic ductal adenocarcinoma focus increasingly on preoperative chemotherapy rather than preoperative chemoradiotherapy. This study aimed to investigate the impact of preoperative chemotherapy and preoperative chemoradiotherapy on postoperative pancreatic fistula and other pancreatic-specific surgery related complications on a nationwide level.

METHODS

All patients after pancreatoduodenectomy for pancreatic ductal adenocarcinoma were included in the mandatory nationwide prospective Dutch Pancreatic Cancer Audit (2014-2020). Baseline and treatment characteristics were compared between immediate surgery, preoperative chemotherapy, and preoperative chemoradiotherapy. The relationship between preoperative chemotherapy, chemoradiotherapy, and clinically relevant postoperative pancreatic fistula (International Study Group of Pancreatic Surgery grade B/C) was investigated using multivariable logistic regression analyses.

RESULTS

Overall, 2,019 patients after pancreatoduodenectomy for pancreatic ductal adenocarcinoma were included, of whom 1,678 underwent immediate surgery (83.1%), 192 (9.5%) received preoperative chemotherapy, and 149 (7.4%) received preoperative chemoradiotherapy. Postoperative pancreatic fistula occurred in 8.3% of patients after immediate surgery, 4.2% after preoperative chemotherapy, and 2.0% after preoperative chemoradiotherapy (P = .004). In multivariable analysis, the use of preoperative chemoradiotherapy was associated with reduced risk of postoperative pancreatic fistula (odds ratio, 0.21; 95% confidence interval, 0.03-0.69; P = .033) compared with immediate surgery, whereas preoperative chemotherapy was not (odds ratio, 0.59; 95% confidence interval, 0.25-1.25; P = .199). Intraoperatively hard, or fibrotic pancreatic texture was most frequently observed after preoperative chemoradiotherapy (53% immediate surgery, 62% preoperative chemotherapy, 77% preoperative chemoradiotherapy, P < .001).

CONCLUSION

This nationwide analysis demonstrated that in patients undergoing pancreatoduodenectomy for pancreatic ductal adenocarcinoma, only preoperative chemoradiotherapy, but not preoperative chemotherapy, was associated with a reduced risk of postoperative pancreatic fistula.

Perineural Invasion is an Important Prognostic Factor in Patients With Radically Resected (R0) and Node-negative (pN0) Pancreatic Cancer

OBJECTIVE

To investigate the association between perineural invasion (PNI) and overall survival (OS) in a nationwide cohort of patients with resected pancreatic ductal adenocarcinoma (PDAC), stratified for margin negative (R0) or positive (R1) resection and absence or presence of lymph node metastasis (pN0 or pN1-N2, respectively).

BACKGROUND

Patients with R0 and pN0 resected PDAC have a relatively favorable prognosis. As PNI is associated with worse OS, this might be a useful factor to provide further prognostic information for patients counselling.

METHODS

A nationwide observational cohort study was performed including all patients who underwent PDAC resection in the Netherlands (2014-2019) with complete information on relevant pathological features (PNI, R status, and N status). OS was assessed using Kaplan-Meier curves, and Cox-proportional hazard analyses were performed to calculate hazard ratio's (HR) with corresponding 95% confidence intervals (CI).

RESULTS

In total, 1630 patients were included with a median follow-up of 43 (interquartile range 33-58) months. PNI was independently associated with worse OS in both R0 patients (HR 1.49 [95%CI 1.18-1.88]; P<0.001) and R1 patients (HR 1.39 [95% CI 1.06-1.83]; P=0.02), as well as in pN0 patients (HR 1.75 [95%CI 1.27-2.41]; P<0.001) and pN1-N2 patients (HR 1.35 [95% CI 1.10-1.67]; P<0.01). In 315 patients with R0N0, multivariable analysis showed that PNI was the strongest predictor of OS (HR 2.24 [95% CI 1.52-3.30]; P<0.001).

CONCLUSION

PNI is strongly associated with worse survival in patients with resected PDAC, in particular in patients with relatively favorable pathological features. These findings may aid patient stratification and counselling and help guide treatment strategies.

Minimum and Optimal CA19-9 Response After Two Months Induction Chemotherapy in Patients With Locally Advanced Pancreatic Cancer: A Nationwide Multicenter Study

OBJECTIVE

This nationwide multicenter study aimed to define clinically relevant thresholds of relative serum CA19-9 response after 2 months of induction chemotherapy in patients with locally advanced pancreatic cancer (LAPC).

BACKGROUND

CA19-9 is seen as leading biomarker for response evaluation in patients with LAPC, but early clinically useful cut-offs are lacking.

METHODS

All consecutive patients with LAPC after 4 cycles (m)FOLFIRINOX or 2 cycles gemcitabine-nab-paclitaxel induction chemotherapy (±radiotherapy) with CA19-9 ≥5 U/mL at baseline were analyzed (2015-2019). The association of CA19-9 response with median OS (mOS) was evaluated for different CA19-9 cut-off points. Minimum and optimal CA19-9 response were established via log-rank test. Predictors for OS were analyzed using COX regression analysis.

RESULTS

Overall, 212 patients were included, of whom 42 (19.8%) underwent resection. Minimum CA19-9 response demonstrating a clinically significant median OS difference (12.7 vs. 19.6 months) was seen at ≥40% CA19-9 decrease. The optimal cutoff for CA19-9 response was ≥60% decrease (21.7 vs. 14.0 mo, P =0.021). Only for patients with elevated CA19-9 levels at baseline (n=184), CA19-9 decrease ≥60% [hazard ratio (HR)=0.59, 95% CI, 0.36-0.98, P =0.042] was independently associated with prolonged OS, as were SBRT (HR=0.42, 95% CI, 0.25-0.70; P =0.001), and resection (HR=0.25, 95% CI, 0.14-0.46, P <0.001), and duration of chemotherapy (HR=0.75, 95% CI, 0.69-0.82, P <0.001).

CONCLUSIONS

CA19-9 decrease of ≥60% following induction chemotherapy as optimal response cut-off in patients with LAPC is an independent predictor for OS when CA19-9 is increased at baseline. Furthermore, ≥40% is the minimum cut-off demonstrating survival benefit. These cut-offs may be used when discussing treatment strategies during early response evaluation.

Implementation of Best Practices in Pancreatic Cancer Care in the Netherlands: A Stepped-Wedge Randomized Clinical Trial

Importance

Implementation of new cancer treatment strategies as recommended by evidence-based guidelines is often slow and suboptimal.

Objective

To improve the implementation of guideline-based best practices in the Netherlands in pancreatic cancer care and assess the impact on survival.

Design, setting, and participants

This multicenter, stepped-wedge cluster randomized trial compared enhanced implementation of best practices with usual care in consecutive patients with all stages of pancreatic cancer. It took place from May 22, 2018 through July 9, 2020. Data were analyzed from April 1, 2022, through February 1, 2023. It included all patients in the Netherlands with pathologically or clinically diagnosed pancreatic ductal adenocarcinoma. This study reports 1-year follow-up (or shorter in case of deceased patients).

Intervention

The 5 best practices included optimal use of perioperative chemotherapy, palliative chemotherapy, pancreatic enzyme replacement therapy (PERT), referral to a dietician, and use of metal stents in patients with biliary obstruction. A 6-week implementation period was completed, in a randomized order, in all 17 Dutch networks for pancreatic cancer care.

Main Outcomes and Measures

The primary outcome was 1-year survival. Secondary outcomes included adherence to best practices and quality of life (European Organisation for Research and Treatment of Cancer [EORTC] global health score).

Results

Overall, 5887 patients with pancreatic cancer (median age, 72.0 [IQR, 64.0-79.0] years; 50% female) were enrolled, 2641 before and 2939 after implementation of best practices (307 during wash-in period). One-year survival was 24% vs 23% (hazard ratio, 0.98, 95% CI, 0.88-1.08). There was no difference in the use of neoadjuvant chemotherapy (11% vs 11%), adjuvant chemotherapy (48% vs 51%), and referral to a dietician (59% vs 63%), while the use of palliative chemotherapy (24% vs 30%; odds ratio [OR], 1.38; 95% CI, 1.10-1.74), PERT (34% vs 45%; OR, 1.64; 95% CI, 1.28-2.11), and metal biliary stents increased (74% vs 83%; OR, 1.78; 95% CI, 1.13-2.80). The EORTC global health score did not improve (area under the curve, 43.9 vs 42.8; median difference, -1.09, 95% CI, -3.05 to 0.94).

Conclusions and Relevance

In this randomized clinical trial, implementation of 5 best practices in pancreatic cancer care did not improve 1-year survival and quality of life. The finding that most patients received no tumor-directed treatment paired with the poor survival highlights the need for more personalized treatment options.

Trial Registration

ClinicalTrials.gov Identifier: NCT03513705.

Nationwide Use and Outcome of Surgery for Locally Advanced Pancreatic Cancer Following Induction Chemotherapy

BACKGROUND

Several international high-volume centers have reported good outcomes after resection of locally advanced pancreatic cancer (LAPC) following chemo(radio)therapy, but it is unclear how this translates to nationwide clinical practice and outcome. This study aims to assess the nationwide use and outcome of resection of LAPC following induction chemo(radio)therapy.

PATIENTS AND METHODS

A multicenter retrospective study including all patients who underwent resection for LAPC following chemo(radio)therapy in all 16 Dutch pancreatic surgery centers (2014-2020), registered in the mandatory Dutch Pancreatic Cancer Audit. LAPC is defined as arterial involvement > 90° and/or portomesenteric venous > 270° involvement or occlusion.

RESULTS

Overall, 142 patients underwent resection for LAPC, of whom 34.5% met the 2022 National Comprehensive Cancer Network criteria. FOLFIRINOX was the most commonly (93.7%) used chemotherapy [median 5 cycles (IQR 4-8)]. Venous and arterial resections were performed in 51.4% and 14.8% of patients. Most resections (73.9%) were performed in high-volume centers (i.e., ≥ 60 pancreatoduodenectomies/year). Overall median volume of LAPC resections/center was 4 (IQR 1-7). In-hospital/30-day major morbidity was 37.3% and 90-day mortality was 4.2%. Median OS from diagnosis was 26 months (95% CI 23-28) and 5-year OS 18%. Surgery in high-volume centers [HR = 0.542 (95% CI 0.318-0.923)], ypN1-2 [HR = 3.141 (95% CI 1.886-5.234)], and major morbidity [HR = 2.031 (95% CI 1.272-3.244)] were associated with OS.

CONCLUSIONS

Resection of LAPC following chemo(radio)therapy is infrequently performed in the Netherlands, albeit with acceptable morbidity, mortality, and OS. Given these findings, a structured nationwide approach involving international centers of excellence would be needed to improve selection of patients with LAPC for surgical resection following induction therapy.

Evaluation of Short- and Long-Term Outcomes After Resection in Patients with Locally Advanced versus (Borderline) Resectable Pancreatic Cancer

OBJECTIVE

This study aims to evaluate short- and long-term outcomes following pancreatectomy in patients with LAPC compared to (B)RPC patients.

SUMMARY BACKGROUND DATA

Selected patients diagnosed with locally advanced pancreatic cancer (LAPC) are increasingly undergoing resection following induction chemotherapy. To evaluate the benefit of this treatment approach, it is helpful to compare outcomes in resected patients with primary LAPC to outcomes in resected patients with primary (borderline) resectable pancreatic cancer ((B)RPC).

METHODS

Two prospectively maintained nationwide databases were used for this study. Patients with (B)RPC undergoing upfront tumor resection and patients with resected LAPC after induction therapy were included. Outcomes were postoperative pancreas-specific complications, 90-day mortality, pathological outcomes, disease-free interval (DFI), and overall survival (OS).

RESULTS

Overall, 879 patients were included; 103 with LAPC (12%) and 776 with (B)RPC (88%). LAPC patients had a lower WHO performance score and CACI. Postoperative pancreas-specific complications were comparable between groups, except delayed gastric emptying grade C, which occurred more often in LAPC patients (9% vs. 3%, P=0.03). Ninety-day mortality was comparable. About half of the patients in both groups (54% in LAPC vs. 48% in (B)RPC), P=0.21) had a radical resection (R0). DFI was 13 months in both groups (P=0.12) and OS from date of diagnosis was 24 months in LAPC patients and 19 months in (B)RPC patients (P=0.34).

CONCLUSIONS

In our nationwide prospective databases, pancreas-specific complications, mortality and survival in patients with LAPC following pancreatectomy are comparable with those undergoing resection for (B)RPC. These outcomes suggest that postoperative morbidity and mortality after tumor resection in carefully selected patients with LAPC are acceptable.

Metabolic Dysfunction-Associated Steatotic Liver Disease in a Dish: Human Precision-Cut Liver Slices as a Platform for Drug Screening and Interventions

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a growing healthcare problem with limited therapeutic options. Progress in this field depends on the availability of reliable preclinical models. Human precision-cut liver slices (PCLSs) have been employed to replicate the initiation of MASLD, but a comprehensive investigation into MASLD progression is still missing. This study aimed to extend the current incubation time of human PCLSs to examine different stages in MASLD. Healthy human PCLSs were cultured for up to 96 h in a medium enriched with high sugar, high insulin, and high fatty acids to induce MASLD. PCLSs displayed hepatic steatosis, characterized by accumulated intracellular fat. The development of hepatic steatosis appeared to involve a time-dependent impact on lipid metabolism, with an initial increase in fatty acid uptake and storage, and a subsequent down-regulation of lipid oxidation and secretion. PCLSs also demonstrated liver inflammation, including increased pro-inflammatory gene expression and cytokine production. Additionally, liver fibrosis was also observed through the elevated production of pro-collagen 1a1 and tissue inhibitor of metalloproteinase-1 (TIMP1). RNA sequencing showed that the tumor necrosis factor alpha (TNFα) signaling pathway and transforming growth factor beta (TGFβ) signaling pathway were consistently activated, potentially contributing to the development of inflammation and fibrosis. In conclusion, the prolonged incubation of human PCLSs can establish a robust ex vivo model for MASLD, facilitating the identification and evaluation of potential therapeutic interventions.

The Value of Biological and Conditional Factors for Staging of Patients with Resectable Pancreatic Cancer Undergoing Upfront Resection: A Nationwide Analysis

BACKGROUND

Novel definitions suggest that resectability status for pancreatic ductal adenocarcinoma (PDAC) should be assessed beyond anatomical criteria, considering both biological and conditional factors. This has, however, yet to be validated on a nationwide scale. This study evaluated the prognostic value of biological and conditional factors for staging of patients with resectable PDAC.

PATIENTS AND METHODS

A nationwide observational cohort study was performed, including all consecutive patients who underwent upfront resection of National Comprehensive Cancer Network resectable PDAC in the Netherlands (2014-2019) with complete information on preoperative carbohydrate antigen (CA) 19-9 and Eastern Cooperative Oncology Group (ECOG) performance status. PDAC was considered biologically unfavorable (RB+) if CA19-9 ≥ 500 U/mL and favorable (RB-) otherwise. ECOG ≥ 2 was considered conditionally unfavorable (RC+) and favorable otherwise (RC-). Overall survival (OS) was assessed using Kaplan-Meier and Cox-proportional hazard analysis, presented as hazard ratios (HRs) with 95% confidence interval (CI).

RESULTS

Overall, 688 patients were analyzed with a median overall survival (OS) of 20 months (95% CI 19-23). OS was 14 months (95% CI 10 months-median not reached) in 20 RB+C+ patients (3%; HR 1.61, 95% CI 0.86-2.70), 13 months (95% CI 11-15) in 156 RB+C- patients (23%; HR 1.86, 95% CI 1.50-2.31), and 21 months (95% CI 12-41) in 47 RB-C+ patients (7%; HR 1.14, 95% CI 0.80-1.62) compared with 24 months (95% CI 22-27) in 465 patients with RB-C- PDAC (68%; reference).

CONCLUSIONS

Survival after upfront resection of anatomically resectable PDAC is worse in patients with CA19-9 ≥ 500 U/mL, while performance status had no impact. This supports consideration of CA19-9 in preoperative staging of resectable PDAC.

Nationwide use and Outcome of Minimally Invasive Distal Pancreatectomy in IDEAL Stage IV following a Training Program and Randomized Trial

OBJECTIVE

To assess the nationwide long-term uptake and outcomes of minimally invasive distal pancreatectomy (MIDP) after a nationwide training program and randomized trial.

BACKGROUND

Two randomized trials demonstrated the superiority of MIDP over open distal pancreatectomy (ODP) in terms of functional recovery and hospital stay. Data on implementation of MIDP on a nationwide level are lacking.

METHODS

Nationwide audit-based study including consecutive patients after MIDP and ODP in 16 centers in the Dutch Pancreatic Cancer Audit (2014 to 2021). The cohort was divided into three periods: early implementation, during the LEOPARD randomized trial, and late implementation. Primary endpoints were MIDP implementation rate and textbook outcome.

RESULTS

Overall, 1496 patients were included with 848 MIDP (56.5%) and 648 ODP (43.5%). From the early to the late implementation period, the use of MIDP increased from 48.6% to 63.0% and of robotic MIDP from 5.5% to 29.7% ( P <0.001). The overall use of MIDP (45% to 75%) and robotic MIDP (1% to 84%) varied widely between centers ( P <0.001). In the late implementation period, 5/16 centers performed >75% of procedures as MIDP. After MIDP, in-hospital mortality and textbook outcome remained stable over time. In the late implementation period, ODP was more often performed in ASA score III-IV (24.9% vs. 35.7%, P =0.001), pancreatic cancer (24.2% vs. 45.9%, P <0.001), vascular involvement (4.6% vs. 21.9%, P <0.001), and multivisceral involvement (10.5% vs. 25.3%, P <0.001). After MIDP, shorter hospital stay (median 7 vs. 8 d, P <0.001) and less blood loss (median 150 vs. 500 mL, P <0.001), but more grade B/C postoperative pancreatic fistula (24.4% vs. 17.2%, P =0.008) occurred as compared to ODP.

CONCLUSION

A sustained nationwide implementation of MIDP after a successful training program and randomized trial was obtained with satisfactory outcomes. Future studies should assess the considerable variation in the use of MIDP between centers and, especially, robotic MIDP.

Continuous Renal Replacement Therapy During Long-term Normothermic Machine Perfusion of Human Donor Livers for up to 7 D

Background

Normothermic machine perfusion (NMP) is used to preserve and test donor livers before transplantation. During NMP, the liver is metabolically active and produces waste products, which are released into the perfusate. In this study, we describe our simplified and inexpensive setup that integrates continuous renal replacement therapy (CRRT) with NMP for up to 7 d. We also investigated if the ultrafiltrate could be used for monitoring perfusate concentrations of small molecules such as glucose and lactate.

Methods

Perfusate composition (urea, osmolarity, sodium, potassium, chloride, calcium, magnesium, phosphate, glucose, and lactate) was analyzed from 56 human NMP procedures without CRRT. Next, in 6 discarded human donor livers, CRRT was performed during NMP by integrating a small dialysis filter (0.2 m2) into the circuit to achieve continuous ultrafiltration combined with continuous fluid substitution for up to 7 d.

Results

Within a few hours of NMP without CRRT, a linear increase in osmolarity and concentrations of urea and phosphate to supraphysiological levels was observed. After integration of CRRT into the NMP circuit, the composition of the perfusate was corrected to physiological values within 12 h, and this homeostasis was maintained during NMP for up to 7 d. Glucose and lactate levels, as measured in the CRRT ultrafiltrate, were strongly correlated with perfusate levels (r = 0.997, P < 0.001 and r = 0.999, P < 0.001, respectively).

Conclusions

The integration of CRRT into the NMP system corrected the composition of the perfusate to near-physiological values, which could be maintained for up to 7 d. The ultrafiltrate can serve as an alternative to the perfusate to monitor concentrations of small molecules without potentially compromising sterility.

Prolonged hypothermic machine perfusion enables daytime liver transplantation - an IDEAL stage 2 prospective clinical trial

Background

Liver transplantation is traditionally performed around the clock to minimize organ ischemic time. However, the prospect of prolonging preservation times holds the potential to streamline logistics and transform liver transplantation into a semi-elective procedure, reducing the need for nighttime surgeries. Dual hypothermic oxygenated machine perfusion (DHOPE) of donor livers for 1-2 h mitigates ischemia-reperfusion injury and improves transplant outcomes. Preclinical studies have shown that DHOPE can safely extend the preservation of donor livers for up to 24 h.

Methods

We conducted an IDEAL stage 2 prospective clinical trial comparing prolonged (≥4 h) DHOPE to conventional (1-2 h) DHOPE for brain-dead donor livers, enabling transplantation the following morning. Liver allocation to each group was based on donor hepatectomy end times. The primary safety endpoint was a composite of all serious adverse events (SAE) within 30 days after transplantation. The primary feasibility endpoint was defined as the number of patients assigned and successfully receiving a prolonged DHOPE-perfused liver graft. Trial registration at: WHO International Clinical Trial Registry Platform, number NL8740.

Findings

Between November 1, 2020 and July 16, 2022, 24 patients were enrolled. The median preservation time was 14.5 h (interquartile range [IQR], 13.9-15.5) for the prolonged group (n = 12) and 7.9 h (IQR, 7.6-8.6) for the control group (n = 12; p = 0.01). In each group, three patients (25%; 95% CI 3.9-46%, p = 1) experienced a SAE. Markers of ischemia-reperfusion injury and oxidative stress in both perfusate and recipients were consistently low and showed no notable discrepancies between the two groups. All patients assigned to either the prolonged group or control group successfully received a liver graft perfused with either prolonged DHOPE or control DHOPE, respectively.

Interpretation

This first-in-human clinical trial demonstrates the safety and feasibility of DHOPE in prolonging the preservation time of donor livers to enable daytime transplantation. The ability to extend the preservation window to up to 20 h using hypothermic oxygenated machine preservation at a 10 °C temperature has the potential to reshape the landscape of liver transplantation.

Funding

University Medical Center Groningen, the Netherlands.

Predicting Long-term Disease-free Survival After Resection of Pancreatic Ductal Adenocarcinoma: A Nationwide Cohort Study

OBJECTIVE

To develop a prediction model for long-term (≥5 years) disease-free survival (DFS) after the resection of pancreatic ductal adenocarcinoma (PDAC).

BACKGROUND

Despite high recurrence rates, ~10% of patients have long-term DFS after PDAC resection. A model to predict long-term DFS may aid individualized prognostication and shared decision-making.

METHODS

This nationwide cohort study included all consecutive patients who underwent PDAC resection in the Netherlands (2014-2016). The best-performing prognostic model was selected by Cox-proportional hazard analysis and Akaike's Information Criterion, presented by hazard ratios (HRs) with 95% confidence intervals (CIs). Internal validation was performed, and discrimination and calibration indices were assessed.

RESULTS

In all, 836 patients with a median follow-up of 67 months (interquartile range 51-79) were analyzed. Long-term DFS was seen in 118 patients (14%). Factors predictive of long-term DFS were low preoperative carbohydrate antigen 19-9 (logarithmic; HR 1.21; 95% CI 1.10-1.32), no vascular resection (HR 1.33; 95% CI 1.12-1.58), T1 or T2 tumor stage (HR 1.52; 95% CI 1.14-2.04, and HR 1.17; 95% CI 0.98-1.39, respectively), well/moderate tumor differentiation (HR 1.44; 95% CI 1.22-1.68), absence of perineural and lymphovascular invasion (HR 1.42; 95% CI 1.11-1.81 and HR 1.14; 95% CI 0.96-1.36, respectively), N0 or N1 nodal status (HR 1.92; 95% CI 1.54-2.40, and HR 1.33; 95% CI 1.11-1.60, respectively), R0 resection margin status (HR 1.25; 95% CI 1.07-1.46), no major complications (HR 1.14; 95% CI 0.97-1.35) and adjuvant chemotherapy (HR 1.74; 95% CI 1.47-2.06). Moderate performance (concordance index 0.68) with adequate calibration (slope 0.99) was achieved.

CONCLUSIONS

The developed prediction model, readily available at www.pancreascalculator.com, can be used to estimate the probability of long-term DFS after resection of pancreatic ductal adenocarcinoma.

Health-related quality of life is linked to the gut microbiome in kidney transplant recipients

Kidney transplant recipients (KTR) have impaired health-related quality of life (HRQoL) and suffer from intestinal dysbiosis. Increasing evidence shows that gut health and HRQoL are tightly related in the general population. Here, we investigate the association between the gut microbiome and HRQoL in KTR, using metagenomic sequencing data from fecal samples collected from 507 KTR. Multiple bacterial species are associated with lower HRQoL, many of which have previously been associated with adverse health conditions. Gut microbiome distance to the general population is highest among KTR with an impaired physical HRQoL (R = -0.20, P = 2.3 × 10-65) and mental HRQoL (R = -0.14, P = 1.3 × 10-3). Physical and mental HRQoL explain a significant part of variance in the gut microbiome (R2 = 0.58%, FDR = 5.43 × 10-4 and R2 = 0.37%, FDR = 1.38 × 10-3, respectively). Additionally, multiple metabolic and neuroactive pathways (gut brain modules) are associated with lower HRQoL. While the observational design of our study does not allow us to analyze causality, we provide a comprehensive overview of the associations between the gut microbiome and HRQoL while controlling for confounders.

Risk Models for Developing Pancreatic Fistula After Pancreatoduodenectomy: Validation in a Nationwide Prospective Cohort

OBJECTIVE

To evaluate the performance of published fistula risk models by external validation, and to identify independent risk factors for postoperative pancreatic fistula (POPF).

BACKGROUND

Multiple risk models have been developed to predict POPF after pancreatoduodenectomy. External validation in high-quality prospective cohorts is, however, lacking or only performed for individual models.

METHODS

A post hoc analysis of data from the stepped-wedge cluster cluster-randomized Care After Pancreatic Resection According to an Algorithm for Early Detection and Minimally Invasive Management of Pancreatic Fistula versus Current Practice (PORSCH) trial was performed. Included were all patients undergoing pancreatoduodenectomy in the Netherlands (January 2018-November 2019). Risk models on POPF were identified by a systematic literature search. Model performance was evaluated by calculating the area under the receiver operating curves (AUC) and calibration plots. Multivariable logistic regression was performed to identify independent risk factors associated with clinically relevant POPF.

RESULTS

Overall, 1358 patients undergoing pancreatoduodenectomy were included, of whom 341 patients (25%) developed clinically relevant POPF. Fourteen risk models for POPF were evaluated, with AUCs ranging from 0.62 to 0.70. The updated alternative fistula risk score had an AUC of 0.70 (95% confidence intervals [CI]: 0.69-0.72). The alternative fistula risk score demonstrated an AUC of 0.70 (95% CI: 0.689-0.71), whilst an AUC of 0.70 (95% CI: 0.699-0.71) was also found for the model by Petrova and colleagues. Soft pancreatic texture, pathology other than pancreatic ductal adenocarcinoma or chronic pancreatitis, small pancreatic duct diameter, higher body mass index, minimally invasive resection and male sex were identified as independent predictors of POPF.

CONCLUSION

Published risk models predicting clinically relevant POPF after pancreatoduodenectomy have a moderate predictive accuracy. Their clinical applicability to identify high-risk patients and guide treatment strategies is therefore questionable.

Bile proteome reveals biliary regeneration during normothermic preservation of human donor livers

Normothermic machine perfusion (NMP) after static cold storage is increasingly used for preservation and assessment of human donor livers prior to transplantation. Biliary viability assessment during NMP reduces the risk of post-transplant biliary complications. However, understanding of molecular changes in the biliary system during NMP remains incomplete. We performed an in-depth, unbiased proteomics analysis of bile collected during sequential hypothermic machine perfusion, rewarming and NMP of 55 human donor livers. Longitudinal analysis during NMP reveals proteins reflective of cellular damage at early stages, followed by upregulation of secretory and immune response processes. Livers with bile chemistry acceptable for transplantation reveal protein patterns implicated in regenerative processes, including cellular proliferation, compared to livers with inadequate bile chemistry. These findings are reinforced by detection of regenerative gene transcripts in liver tissue before machine perfusion. Our comprehensive bile proteomics and liver transcriptomics data sets provide the potential to further evaluate molecular mechanisms during NMP and refine viability assessment criteria.

Normothermic Machine-perfused Human Donor Livers Produce Functional Hemostatic Proteins

BACKGROUND

Normothermic machine perfusion (NMP) is used for the viability assessment of high-risk donor livers before transplantation. The production of hemostatic proteins is one of the major synthetic functions of the liver. The objective of this study was to measure the concentration and functionality of hemostatic proteins concentration in the NMP perfusate of human donor livers.

METHODS

Thirty-six livers that underwent NMP for viability assessment were included in this study. Perfusate samples taken during NMP (start, 150 min, and 300 min) were used for the measurement of antigen and activity levels of hemostatic proteins (factors II, VII, and X; fibrinogen; plasminogen; antithrombin; tissue plasminogen activator; von Willebrand factor; and proteins induced by vitamin K absence). The antigen levels were correlated with hepatocellular function according to previously proposed individual hepatocellular viability criteria: lactate clearance and perfusate pH.

RESULTS

Antigen levels of hemostatic proteins reached subphysiological levels in the NMP perfusate. Hemostatic proteins that were produced during NMP were at least partially active. All livers produced all hemostatic proteins tested within 150 min of NMP. Hemostatic protein concentrations did not significantly correlate with perfusate lactate and perfusate pH after 150 min of NMP.

CONCLUSIONS

All livers produce functional hemostatic proteins during NMP. The generation of a functional hemostatic system in NMP perfusate confirms the need for adequate anticoagulation of the perfusate to avoid generation of (micro)thrombi that may harm the graft.

Growth differentiation factor 7 autocrine signaling promotes hepatic progenitor cell expansion in liver fibrosis

BACKGROUND AND AIM

Liver fibrosis is prevalent among chronic diseases of the liver and represents a major health burden worldwide. Growth differentiation factor 7 (GDF7), a member of the TGFβ protein superfamily, has been recently investigated for its role in repair of injured organs, but its role in chronic liver diseases remains unclear. Here, we examined hepatic GDF7 expression and its association with development and progression of human liver fibrosis. Moreover, we determined the source and target cells of GDF7 in the human liver.

METHODS

GDF7 expression was analyzed in fibrotic and healthy human liver tissues by immunohistochemistry and qPCR. Cell-specific accumulation of GDF7 was examined by immunofluorescence through co-staining of cell type-specific markers on formalin-fixed paraffin-embedded human liver tissues. Public single cell RNA sequence databases were analyzed for cell type-specific expression of GDF7. In vitro, human liver organoids and LX-2 hepatic stellate cells (LX-2) were treated with recombinant human GDF7. Human liver organoids were co-cultured with activated LX-2 cells to induce an autocrine signaling circuit of GDF7 in liver organoids.

RESULTS

GDF7 protein levels were elevated in fibrotic liver tissue, mainly detected in hepatocytes and cholangiocytes. In line, GDF7 mRNA was mainly detected in liver parenchymal cells. Expressions of BMPR1A and BMPR2, encoding GDF7 receptors, were readily detected in hepatocytes, cholangiocytes and stellate cells in vivo and in vitro. In vitro, recombinant GDF7 promoted liver organoid growth and enhanced expression of the progenitor cell markers (LGR5, AXIN2), but failed to activate LX-2 cells. Still, activated LX-2 cells induced GDF7 and LGR5 expression in co-cultured human liver organoids.

CONCLUSIONS

Collectively, this study reveals a role of GDF7 in liver fibrosis and suggests a potential pro-regenerative function that can be utilized for amelioration of hepatic fibrosis caused by chronic liver disease.

Population-based impact of COVID-19 on incidence, treatment, and survival of patients with pancreatic cancer

BACKGROUND

The COVID-19 pandemic has put substantial strain on the healthcare system of which the effects are only partly elucidated. This study aimed to investigate the impact on pancreatic cancer care.

METHODS

All patients diagnosed with pancreatic cancer between 2017 and 2020 were selected from the Netherlands Cancer Registry. Patients diagnosed and/or treated in 2020 were compared to 2017-2019. Monthly incidence was calculated. Patient, tumor and treatment characteristics were analyzed and compared using Chi-squared tests. Survival data was analyzed using Kaplan-Meier and Log-rank tests.

RESULTS

In total, 11019 patients were assessed. The incidence in quarter (Q)2 of 2020 was comparable with that in Q2 of 2017-2019 (p = 0.804). However, the incidence increased in Q4 of 2020 (p = 0.031), mainly due to a higher incidence of metastatic disease (p = 0.010). Baseline characteristics, surgical resection (15% vs 16%; p = 0.466) and palliative systemic therapy rates (23% vs 24%; p = 0.183) were comparable. In 2020, more surgically treated patients received (neo)adjuvant treatment compared to 2017-2019 (73% vs 67%; p = 0.041). Median overall survival was comparable (3.8 vs 3.8 months; p = 0.065).

CONCLUSION

This nationwide study found a minor impact of the COVID-19 pandemic on pancreatic cancer care and outcome. The Dutch health care system was apparently able to maintain essential care for patients with pancreatic cancer.

Practice variation in venous resection during pancreatoduodenectomy for pancreatic cancer: A nationwide cohort study

BACKGROUND

Practice variation exists in venous resection during pancreatoduodenectomy, but little is known about the potential causes and consequences as large studies are lacking. This study explores the potential causes and consequences of practice variation in venous resection during pancreatoduodenectomy for pancreatic cancer in the Netherlands.

METHODS

This nationwide retrospective cohort study included patients undergoing pancreatoduodenectomy for pancreatic cancer in 18 centers from 2013 through 2017.

RESULTS

Among 1,311 patients undergoing pancreatoduodenectomy, 351 (27%) had a venous resection, and the overall median annual center volume of venous resection was 4. No association was found between the center volume of pancreatoduodenectomy and the rate of venous resections, nor between patient and tumor characteristics and the rate of venous resections per center. Female sex, lower body mass index, neoadjuvant therapy, venous involvement, and stenosis on imaging were predictive for venous resection. Adjusted for these factors, 3 centers performed significantly more, and 3 centers performed significantly fewer venous resections than expected. In patients with venous resection, significantly less major morbidity (22% vs 38%) and longer overall survival (median 16 vs 12 months) were observed in centers with an above-median annual volume of venous resections (>4).

CONCLUSION

Patient and tumor characteristics did not explain significant practice variation between centers in the Netherlands in venous resection during pancreatoduodenectomy for pancreatic cancer. The clinical outcomes of venous resection might be related to the volume of the procedure.

Predictive value of baseline serum carbohydrate antigen 19-9 level on treatment effect of neoadjuvant chemoradiotherapy in patients with resectable and borderline resectable pancreatic cancer in two randomized trials

BACKGROUND

Guidelines suggest that the serum carbohydrate antigen (CA19-9) level should be used when deciding on neoadjuvant treatment in patients with resectable and borderline resectable pancreatic ductal adenocarcinoma (hereafter referred to as pancreatic cancer). In patients with resectable pancreatic cancer, neoadjuvant therapy is advised when the CA19-9 level is 'markedly elevated'. This study investigated the impact of baseline CA19-9 concentration on the treatment effect of neoadjuvant chemoradiotherapy (CRT) in patients with resectable and borderline resectable pancreatic cancers.

METHODS

In this post hoc analysis, data were obtained from two RCTs that compared neoadjuvant CRT with upfront surgery in patients with resectable and borderline resectable pancreatic cancers. The effect of neoadjuvant treatment on overall survival was compared between patients with a serum CA19-9 level above or below 500 units/ml using the interaction test.

RESULTS

Of 296 patients, 179 were eligible for analysis, 90 in the neoadjuvant CRT group and 89 in the upfront surgery group. Neoadjuvant CRT was associated with superior overall survival (HR 0.67, 95 per cent c.i. 0.48 to 0.94; P = 0.019). Among 127 patients (70, 9 per cent) with a low CA19-9 level, median overall survival was 23.5 months with neoadjuvant CRT and 16.3 months with upfront surgery (HR 0.63, 0.42 to 0.93). For 52 patients (29 per cent) with a high CA19-9 level, median overall survival was 15.5 months with neoadjuvant CRT and 12.9 months with upfront surgery (HR 0.82, 0.45 to 1.49). The interaction test for CA19-9 level exceeding 500 units/ml on the treatment effect of neoadjuvant CRT was not significant (P = 0.501).

CONCLUSION

Baseline serum CA19-9 level defined as either high or low has prognostic value, but was not associated with the treatment effect of neoadjuvant CRT in patients with resectable and borderline resectable pancreatic cancers, in contrast with current guideline advice.

Fistula Risk Score for Auditing Pancreatoduodenectomy: The Auditing-FRS

OBJECTIVE

To develop a fistula risk score for auditing, to be able to compare postoperative pancreatic fistula (POPF) after pancreatoduodenectomy among hospitals.

BACKGROUND

For proper comparisons of outcomes in surgical audits, case-mix variation should be accounted for.

METHODS

This study included consecutive patients after pancreatoduodenectomy from the mandatory nationwide Dutch Pancreatic Cancer Audit. Derivation of the score was performed with the data from 2014 to 2018 and validation with 2019 to 2020 data. The primary endpoint of the study was POPF (grade B or C). Multivariable logistic regression analysis was performed for case-mix adjustment of known risk factors.

RESULTS

In the derivation cohort, 3271 patients were included, of whom 479 (14.6%) developed POPF. Male sex [odds ratio (OR)=1.34; 95% confidence interval (CI): 1.09-1.66], higher body mass index (OR=1.07; 95% CI: 1.05-1.10), a final diagnosis other than pancreatic ductal adenocarcinoma/pancreatitis (OR=2.41; 95% CI: 1.90-3.06), and a smaller duct diameter (OR=1.43/mm decrease; 95% CI: 1.32-1.55) were independently associated with POPF. Diabetes mellitus (OR=0.73; 95% CI: 0.55-0.98) was independently associated with a decreased risk of POPF. Model discrimination was good with a C -statistic of 0.73 in the derivation cohort and 0.75 in the validation cohort (n=913). Hospitals differed in particular in the proportion of pancreatic ductal adenocarcinoma/pancreatitis patients, ranging from 36.0% to 58.1%. The observed POPF risk per center ranged from 2.9% to 25.4%. The expected POPF rate based on the 5 risk factors ranged from 11.6% to 18.0% among hospitals.

CONCLUSIONS

The auditing fistula risk score was successful in case-mix adjustment and enables fair comparisons of POPF rates among hospitals.

The international normalised ratio to monitor coagulation factor production during normothermic machine perfusion of human donor livers

BACKGROUND

Normothermic machine perfusion (NMP) of donor livers allows for new diagnostic and therapeutic strategies. As the liver produces most of the haemostatic proteins, coagulation assays such as the International Normalised Ratio (INR) performed in perfusate may be useful to assess hepatocellular function of donor livers undergoing NMP. However, high concentrations of heparin and low levels of fibrinogen may affect coagulation assays.

METHODS

Thirty donor livers that underwent NMP were retrospectively included in this study, of which 18 were subsequently transplanted. We measured INRs in perfusate in presence or absence of exogenously added fibrinogen and/or polybrene. Additionally, we prospectively included 14 donor livers that underwent NMP (of which 11 were transplanted) and measured INR using both a laboratory coagulation analyser and a point-of-care device.

RESULTS

In untreated perfusate samples, the INR was above the detection limit in all donor livers. Addition of both fibrinogen and polybrene was required for adequate INR assessment. INRs decreased over time and detectable perfusate INR values were found in 17/18 donor livers at the end of NMP. INR results were similar between the coagulation analyser and the point-of-care device, but did not correlate with established hepatocellular viability criteria.

CONCLUSIONS

Most of the donor livers that were transplanted showed a detectable perfusate INR at the end of NMP, but samples require processing to allow for INR measurements using laboratory coagulation analysers. Point-of-care devices bypass this need for processing. The INR does not correlate with established viability criteria and might therefore have additional predictive value.

Restoration of Bile Duct Injury of Donor Livers During Ex Situ Normothermic Machine Perfusion

BACKGROUND

End-ischemic ex situ normothermic machine perfusion (NMP) enables assessment of donor livers prior to transplantation. The objective of this study was to provide support for bile composition as a marker of biliary viability and to investigate whether bile ducts of high-risk human donor livers already undergo repair during NMP.

METHODS

Forty-two livers that were initially declined for transplantation were included in our NMP clinical trial. After NMP, livers were either secondary declined (n = 17) or accepted for transplantation (n = 25) based on the chemical composition of bile and perfusate samples. Bile duct biopsies were taken before and after NMP and assessed using an established histological injury severity scoring system and a comprehensive immunohistochemical assessment focusing on peribiliary glands (PBGs), vascular damage, and regeneration.

RESULTS

Bile ducts of livers that were transplanted after viability testing during NMP showed better preservation of PBGs, (micro)vasculature, and increased cholangiocyte proliferation, compared with declined livers. Biliary bicarbonate, glucose, and pH were confirmed as accurate biomarkers of bile duct vitality. In addition, we found evidence of PBG-based progenitor cell differentiation toward mature cholangiocytes during NMP.

CONCLUSIONS

Favorable bile chemistry during NMP correlates well with better-preserved biliary microvasculature and PBGs, with a preserved capacity for biliary regeneration. During NMP, biliary tree progenitor cells start to differentiate toward mature cholangiocytes, facilitating restoration of the ischemically damaged surface epithelium.

Chyle Leak After Pancreatoduodenectomy: Clinical Impact and Risk Factors in a Nationwide Analysis

OBJECTIVE

The aim of this study was to assess the clinical impact and risk factors of chyle leak (CL).

BACKGROUND

In 2017, the International Study Group for Pancreatic Surgery (ISGPS) published the consensus definition of CL. Multicenter series validating this definition are lacking and previous studies investigating risk factors have used different definitions and showed heterogeneous results.

METHODS

This observational cohort study included all consecutive patients after pancreatoduodenectomy in all 19 centers in the mandatory nationwide Dutch Pancreatic Cancer Audit (2017-2019). The primary endpoint was CL (ISGPS grade B/C). Multivariable logistic regression analyses were performed.

RESULTS

Overall, 2159 patients after pancreatoduodenectomy were included. The rate of CL was 7.0% (n=152), including 6.9% (n=150) grade B and 0.1% (n=2) grade C. CL was independently associated with a prolonged hospital stay [odds ratio (OR)=2.84, 95% confidence interval (CI): 1.85-4.36, P <0.001] but not with mortality (OR=0.3, 95% CI: 0.0-2.3, P =0.244). In multivariable analyses, independent predictors for CL were vascular resection (OR=2.1, 95% CI: 1.4-3.2, P <0.001) and open surgery (OR=3.5, 95% CI: 1.7-7.2, P =0.001). The number of resected lymph nodes and aortocaval lymph node sampling were not identified as predictors in multivariable analysis.

CONCLUSIONS

In this nationwide analysis, the rate of ISGPS grade B/C CL after pancreatoduodenectomy was 7.0%. Although CL is associated with a prolonged hospital stay, the clinical impact is relatively minor in the vast majority (>98%) of patients. Vascular resection and open surgery are predictors of CL.

Mitochondrial DNA methylation in metabolic associated fatty liver disease

Introduction

Hepatic lipid accumulation and mitochondrial dysfunction are hallmarks of metabolic associated fatty liver disease (MAFLD), yet molecular parameters underlying MAFLD progression are not well understood. Differential methylation within the mitochondrial DNA (mtDNA) has been suggested to be associated with dysfunctional mitochondria, also during progression to Metabolic Steatohepatitis (MeSH). This study further investigates whether mtDNA methylation is associated with hepatic lipid accumulation and MAFLD.

Methods

HepG2 cells were constructed to stably express mitochondria-targeted viral and prokaryotic cytosine DNA methyltransferases (mtM.CviPI or mtM.SssI for GpC or CpG methylation, respectively). A catalytically inactive variant (mtM.CviPI-Mut) was constructed as a control. Mouse and human patients' samples were also investigated. mtDNA methylation was assessed by pyro- or nanopore sequencing.

Results and discussion

Differentially induced mtDNA hypermethylation impaired mitochondrial gene expression and metabolic activity in HepG2-mtM.CviPI and HepG2-mtM.SssI cells and was associated with increased lipid accumulation, when compared to the controls. To test whether lipid accumulation causes mtDNA methylation, HepG2 cells were subjected to 1 or 2 weeks of fatty acid treatment, but no clear differences in mtDNA methylation were detected. In contrast, hepatic Nd6 mitochondrial gene body cytosine methylation and Nd6 gene expression were increased in mice fed a high-fat high cholesterol diet (HFC for 6 or 20 weeks), when compared to controls, while mtDNA content was unchanged. For patients with simple steatosis, a higher ND6 methylation was confirmed using Methylation Specific PCR, but no additional distinctive cytosines could be identified using pyrosequencing. This study warrants further investigation into a role for mtDNA methylation in promoting mitochondrial dysfunction and impaired lipid metabolism in MAFLD.

Branched Chain Amino Acids Are Associated with Physical Performance in Patients with End-Stage Liver Disease

Decreased circulating branched chain amino acids (BCAA) represent a prominent change in amino acid profiles in patients with end-stage liver disease (ESLD). These alterations are considered to contribute to sarcopenia and hepatic encephalopathy and may relate to poor prognosis. Here, we cross-sectionally analyzed the association between plasma BCAA levels and the severity of ESLD and muscle function in participants of the liver transplant subgroup of TransplantLines, enrolled between January 2017 and January 2020. Plasma BCAA levels were measured by nuclear magnetic resonance spectroscopy. Physical performance was analyzed with a hand grip strength test, 4 m walking test, sit-to-stand test, timed up and go test, standing balance test and clinical frailty scale. We included 92 patients (65% men). The Child Pugh Turcotte classification was significantly higher in the lowest sex-stratified BCAA tertile compared to the highest tertile (p = 0.015). The times for the sit-to-stand (r = -0.352, p < 0.05) and timed up and go tests (r = -0.472, p < 0.01) were inversely correlated with total BCAA levels. In conclusion, lower circulating BCAA are associated with the severity of liver disease and impaired muscle function. This suggests that BCAA may represent a useful prognostic marker in the staging of liver disease severity.

Surgical Outcome After Pancreatoduodenectomy for Duodenal Adenocarcinoma Compared with Other Periampullary Cancers: A Nationwide Audit Study

BACKGROUND

Surgical outcome after pancreatoduodenectomy for duodenal adenocarcinoma could differ from pancreatoduodenectomy for other cancers, but large multicenter series are lacking. This study aimed to determine surgical outcome in patients after pancreatoduodenectomy for duodenal adenocarcinoma, compared with other periampullary cancers, in a nationwide multicenter cohort.

METHODS

After pancreatoduodenectomy for cancer between 2014 and 2019, consecutive patients were included from the nationwide, mandatory Dutch Pancreatic Cancer Audit. Patients were stratified by diagnosis. Baseline, treatment characteristics, and postoperative outcome were compared between groups. The association between diagnosis and major complications (Clavien-Dindo grade III or higher) was assessed via multivariable regression analysis.

RESULTS

Overall, 3113 patients, after pancreatoduodenectomy for cancer, were included in this study: 264 (8.5%) patients with duodenal adenocarcinomas and 2849 (91.5%) with other cancers. After pancreatoduodenectomy for duodenal adenocarcinoma, patients had higher rates of major complications (42.8% vs. 28.6%; p < 0.001), postoperative pancreatic fistula (International Study Group of Pancreatic Surgery [ISGPS] grade B/C; 23.1% vs. 13.4%; p < 0.001), complication-related intensive care admission (14.3% vs. 10.3%; p = 0.046), re-interventions (39.8% vs. 26.6%; p < 0.001), in-hospital mortality (5.7% vs. 3.1%; p = 0.025), and longer hospital stay (15 days vs. 11 days; p < 0.001) compared with pancreatoduodenectomy for other cancers. In multivariable analysis, duodenal adenocarcinoma was independently associated with major complications (odds ratio 1.14, 95% confidence interval 1.03-1.27; p = 0.011).

CONCLUSION

Pancreatoduodenectomy for duodenal adenocarcinoma is associated with higher rates of major complications, pancreatic fistula, re-interventions, and in-hospital mortality compared with patients undergoing pancreatoduodenectomy for other cancers. These findings should be considered in patient counseling and postoperative management.

Impact of complications after resection of pancreatic cancer on disease recurrence and survival, and mediation effect of adjuvant chemotherapy: nationwide, observational cohort study

BACKGROUND

The causal pathway between complications after pancreatic cancer resection and impaired long-term survival remains unknown. The aim of this study was to investigate the impact of complications after pancreatic cancer resection on disease-free interval and overall survival, with adjuvant chemotherapy as a mediator.

METHODS

This observational study included all patients undergoing pancreatic cancer resection in the Netherlands (2014-2017). Clinical data were extracted from the prospective Dutch Pancreatic Cancer Audit. Recurrence and survival data were collected additionally. In causal mediation analysis, direct and indirect effect estimates via adjuvant chemotherapy were calculated.

RESULTS

In total, 1071 patients were included. Major complications (hazards ratio 1.22 (95 per cent c.i. 1.04 to 1.43); P = 0.015 and hazards ratio 1.25 (95 per cent c.i. 1.08 to 1.46); P = 0.003) and organ failure (hazards ratio 1.86 (95 per cent c.i. 1.32 to 2.62); P < 0.001 and hazards ratio 1.89 (95 per cent c.i. 1.36 to 2.63); P < 0.001) were associated with shorter disease-free interval and overall survival respectively. The effects of major complications and organ failure on disease-free interval (-1.71 (95 per cent c.i. -2.27 to -1.05) and -3.05 (95 per cent c.i. -4.03 to -1.80) respectively) and overall survival (-1.92 (95 per cent c.i. -2.60 to -1.16) and -3.49 (95 per cent c.i. -4.84 to -2.03) respectively) were mediated by adjuvant chemotherapy. Additionally, organ failure directly affected disease-free interval (-5.38 (95 per cent c.i. -9.27 to -1.94)) and overall survival (-6.32 (95 per cent c.i. -10.43 to -1.99)). In subgroup analyses, the association was found in patients undergoing pancreaticoduodenectomy, but not in patients undergoing distal pancreatectomy.

CONCLUSION

Major complications, including organ failure, negatively impact survival in patients after pancreatic cancer resection, largely mediated by adjuvant chemotherapy. Prevention or adequate treatment of complications and use of neoadjuvant treatment may improve oncological outcomes.

Role of neoadjuvant chemoradiotherapy in liver transplantation for unresectable perihilar cholangiocarcinoma: multicentre, retrospective cohort study

BACKGROUND

The Mayo protocol for liver transplantation in patients with unresectable perihilar cholangiocarcinoma is based on strict selection and neoadjuvant chemoradiotherapy. The role of neoadjuvant chemoradiotherapy in this scenario remains unclear. The aim of this study was to compare outcomes after transplantation for perihilar cholangiocarcinoma using strict selection criteria, either with or without neoadjuvant chemoradiotherapy.

METHODS

This was an international, multicentre, retrospective cohort study of patients who underwent transplantation between 2011 and 2020 for unresectable perihilar cholangiocarcinoma using the Mayo selection criteria and receiving neoadjuvant chemoradiotherapy or not receiving neoadjuvant chemoradiotherapy. Endpoints were post-transplant survival, post-transplant morbidity rate, and time to recurrence.

RESULTS

Of 49 patients who underwent liver transplantation for perihilar cholangiocarcinoma, 27 received neoadjuvant chemoradiotherapy and 22 did not. Overall 1-, 3-, and 5-year post-transplantation survival rates were 65 per cent, 51 per cent and 41 per cent respectively in the group receiving neoadjuvant chemoradiotherapy and 91 per cent, 68 per cent and 53 per cent respectively in the group not receiving neoadjuvant chemoradiotherapy (1-year hazards ratio (HR) 4.55 (95 per cent c.i. 0.98 to 21.13), P = 0.053; 3-year HR 2.07 (95 per cent c.i. 0.78 to 5.54), P = 0.146; 5-year HR 1.71 (95 per cent c.i. 0.71 to 4.09), P = 0.229). Hepatic vascular complications were more frequent in the group receiving neoadjuvant chemoradiotherapy compared with the group not receiving neoadjuvant chemoradiotherapy (nine of 27 versus two of 22, P = 0.045). In multivariable analysis, tumour recurrence occurred less frequently in the group receiving neoadjuvant chemoradiotherapy (HR 0.30 (95 per cent c.i. 0.09 to 0.97), P = 0.044).

CONCLUSION

In selected patients undergoing liver transplantation for perihilar cholangiocarcinoma, neoadjuvant chemoradiotherapy resulted in a lower risk of tumour recurrence, but was associated with a higher rate of early hepatic vascular complications. Adjustments in neoadjuvant chemoradiotherapy reducing the risk of hepatic vascular complications, such as omitting radiotherapy, may further improve the outcome in patients undergoing liver transplantation for perihilar cholangiocarcinoma.

Proton Pump Inhibitor Use, Fatigue, and Health-Related Quality of Life in Kidney Transplant Recipients: Results From the TransplantLines Biobank and Cohort Study

RATIONALE & OBJECTIVE

Prior studies report that the use of proton pump inhibitors (PPIs) can adversely affect gut microbiota and gastrointestinal uptake of micronutrients, in particular iron and magnesium, and are used frequently by kidney transplant recipients. Altered gut microbiota, iron deficiency, and magnesium deficiency have been implicated in the pathogenesis of chronic fatigue. Therefore, we hypothesized that PPI use may be an important and underappreciated cause of fatigue and reduced health-related quality of life (HRQoL) in this population.

STUDY DESIGN

Cross-sectional study.

SETTING & PARTICIPANTS

Kidney transplant recipients (≥1 year after transplantation) enrolled in the TransplantLines Biobank and Cohort Study.

EXPOSURE

PPI use, PPI type, PPI dosage, and duration of PPI use.

OUTCOME

Fatigue and HRQoL, assessed using the validated Checklist Individual Strength 20 Revised questionnaire and Short Form-36 questionnaire.

ANALYTICAL APPROACH

Logistic and linear regression.

RESULTS

We included 937 kidney transplant recipients (mean age 56±13 years, 39% female) at a median of 3 (1-10) years after transplantation. PPI use was associated with fatigue severity (regression coefficient 4.02, 95% CI, 2.18 to 5.85, P<0.001), a higher risk of severe fatigue (OR 2.05, 95% CI, 1.48 to 2.84, P<0.001), lower physical HRQoL (regression coefficient-8.54, 95% CI, -11.54 to-5.54, P<0.001), and lower mental HRQoL (regression coefficient-4.66, 95% CI, -7.15 to-2.17, P<0.001). These associations were independent of potential confounders including age, time since transplantation, history of upper gastrointestinal disease, antiplatelet therapy, and the total number of medications. They were present among all individually assessed PPI types and were dose dependent. Duration of PPI exposure was only associated with fatigue severity.

LIMITATIONS

Residual confounding and inability to assess causal relationships.

CONCLUSIONS

PPI use is independently associated with fatigue and lower HRQoL among kidney transplant recipients. PPI use might be an easily accessible target for alleviating fatigue and improving HRQoL among kidney transplant recipients. Further studies examining the effect of PPI exposure in this population are warranted.

Waitlist mortality of young patients with biliary atresia: Impact of allocation policy and living donor liver transplantation

Patients with biliary atresia (BA) below 2 years of age in need of a transplantation largely rely on partial grafts from deceased donors (deceased donor liver transplantation [DDLT]) or living donors (living donor liver transplantation [LDLT]). Because of high waitlist mortality in especially young patients with BA, the Eurotransplant Liver Intestine Advisory Committee (ELIAC) has further prioritized patients with BA listed before their second birthday for allocation of a deceased donor liver since 2014. We evaluated whether this Eurotransplant (ET) allocation prioritization changed the waitlist mortality of young patients with BA. We used a pre-post cohort study design with the implementation of the new allocation rule between the two periods. Participants were patients with BA younger than 2 years who were listed for liver transplantation in the ET database between 2001 and 2018. Competing risk analyses were performed to assess waitlist mortality in the first 2 years after listing. We analyzed a total of 1055 patients with BA, of which 882 had been listed in the preimplementation phase (PRE) and 173 in the postimplementation phase (POST). Waitlist mortality decreased from 6.7% in PRE to 2.3% in POST ( p = 0.03). Interestingly, the proportion of young patients with BA undergoing DDLT decreased from 32% to 18% after ET allocation prioritization ( p = 0.001), whereas LDLT increased from 55% to 74% ( p = 0.001). The proportional increase in LDLT decreased the median waitlist duration of transplanted patients from 1.5 months in PRE to 0.85 months in POST ( p = 0.003). Since 2014, waitlist mortality in young patients with BA has strongly decreased in the ET region. Rather than associated with prioritized allocation of deceased donor organs, the decreased waitlist mortality was related to a higher proportion of patients undergoing LDLT.

High plasma levels of betaine, a trimethylamine N-Oxide-related metabolite, are associated with the severity of cirrhosis

BACKGROUND AND AIMS

The gut microbiome-related metabolites betaine and trimethylamine N-oxide (TMAO) affect major health issues. In cirrhosis, betaine metabolism may be diminished because of impaired hepatic betaine homocysteine methyltransferase activity, whereas TMAO generation from trimethylamine may be altered because of impaired hepatic flavin monooxygenase expression. Here, we determined plasma betaine and TMAO levels in patients with end-stage liver disease and assessed their relationships with liver disease severity.

METHODS

Plasma betaine and TMAO concentrations were measured by nuclear magnetic resonance spectroscopy in 129 cirrhotic patients (TransplantLines cohort study; NCT03272841) and compared with levels from 4837 participants of the PREVEND cohort study. Disease severity was assessed by Child-Pugh-Turcotte (CPT) classification and Model for End-stage Liver Disease (MELD) score.

RESULTS

Plasma betaine was on average 60% higher (p < .001), whereas TMAO was not significantly lower in cirrhotic patients vs. PREVEND population (p = .44). After liver transplantation (n = 13), betaine decreased (p = .017; p = .36 vs. PREVEND population), whereas TMAO levels tended to increase (p = .085) to higher levels than in the PREVEND population (p = .003). Betaine levels were positively associated with the CPT stage and MELD score (both p < .001). The association with the MELD score remained in the fully adjusted analysis (p < .001). The association of TMAO with the MELD score did not reach significance (p = .11). Neither betaine nor TMAO levels were associated with mortality on the waiting list for liver transplantation (adjusted p = .78 and p = .44, respectively).

CONCLUSION

Plasma betaine levels are elevated in cirrhotic patients in parallel with disease severity and decrease after liver transplantation.

A nationwide assessment of hepatocellular adenoma resection: Indications and pathological discordance

Hepatocellular adenomas (HCAs) are benign liver tumors associated with bleeding or malignant transformation. Data on the indication for surgery are scarce. We analyzed indications and outcome of patients operated for HCAs < 50 mm compared to HCAs ≥ 50 mm. Changes in final postoperative diagnosis were assessed. We performed a retrospective study that included patients who underwent resection for (suspected) HCAs in the Netherlands from 2014 to 2019. Indication for resection was analyzed and stratified for small (<50 mm) and large (≥50 mm) tumors. Logistic regression analysis was performed on factors influencing change in tumor diagnosis. Out of 222 patients who underwent surgery, 44 (20%) patients had a tumor <50 mm. Median age was 46 (interquartile range [IQR], 33-56) years in patients with small tumors and 37 (IQR, 31-46) years in patients with large tumors ( p  = 0.016). Patients with small tumors were more frequently men (21% vs. 5%, p  = 0.002). Main indications for resection in patients with small tumors were suspicion of (pre)malignancy (55%), (previous) bleeding (14%), and male sex (11%). Patients with large tumors received operations because of tumor size >50 mm (52%), suspicion of (pre)malignancy (28%), and (previous) bleeding (5.1%). No difference was observed in HCA-subtype distribution between small and large tumors. Ninety-six (43%) patients had a postoperative change in diagnosis. Independent risk factors for change in diagnosis were tumor size <50 mm (adjusted odds ratio [aOR], 3.4; p  < 0.01), male sex (aOR, 3.7; p  = 0.03), and lack of hepatobiliary contrast-enhanced magnetic resonance imaging (CE-MRI) (aOR, 1.8; p  = 0.04). Resection for small (suspected) HCAs was mainly indicated by suspicion of (pre)malignancy, whereas for large (suspected) HCAs, tumor size was the most prevalent indication. Male sex, tumor size <50 mm, and lack of hepatobiliary CE-MRI were independent risk factors for postoperative change in tumor diagnosis.

Intraoperative Molecular Fluorescence Imaging of Pancreatic Cancer by Targeting Vascular Endothelial Growth Factor: A Multicenter Feasibility Dose-Escalation Study

Tumor visualization with near-infrared fluorescence (NIRF) imaging might aid exploration and resection of pancreatic cancer by visualizing the tumor in real time. Conjugation of the near-infrared fluorophore IRDye800CW to the monoclonal antibody bevacizumab enables targeting of vascular endothelial growth factor A. The aim of this study was to determine whether intraoperative tumor-specific imaging of pancreatic cancer with the fluorescent tracer bevacizumab-800CW is feasible and safe. Methods: In this multicenter dose-escalation phase I trial, patients in whom pancreatic ductal adenocarcinoma (PDAC) was suspected were administered bevacizumab-800CW (4.5, 10, or 25 mg) 3 d before surgery. Safety monitoring encompassed allergic or anaphylactic reactions and serious adverse events attributed to bevacizumab-800CW. Intraoperative NIRF imaging was performed immediately after laparotomy, just before and after resection of the specimen. Postoperatively, fluorescence signals on the axial slices and formalin-fixed paraffin-embedded tissue blocks from the resected specimens were correlated with histology. Subsequently, tumor-to-background ratios (TBR) were calculated. Results: Ten patients with clinically suspected PDAC were enrolled in the study. Four of the resected specimens were confirmed PDACs; other malignancies were distal cholangiocarcinoma, ampullary carcinoma, and neuroendocrine tumors. No serious adverse events were related to bevacizumab-800CW. In vivo tumor visualization with NIRF imaging differed per tumor type and was nonconclusive. Ex vivo TBRs were 1.3, 1.5, and 2.5 for the 4.5-, 10-, and 25-mg groups, respectively. Conclusion: NIRF-guided surgery in patients with suspected PDAC using bevacizumab-IRDye800CW is feasible and safe. However, suboptimal TBRs were obtained because no clear distinction between pancreatic cancer from normal or inflamed pancreatic tissue was achieved. Therefore, a more tumor-specific tracer than bevacizumab-IRDye800CW for PDAC is preferred.

Tremor, Daily Functioning, and Health-Related Quality of Life in Solid Organ Transplant Recipients

Solid organ transplant recipients (SOTR) frequently report tremor. Data concerning tremor-related impairment and its potential impact on health-related quality of life (HRQoL) are lacking. This cross-sectional study assesses impact of tremor on activities of daily living and HRQoL using validated questionnaires among SOTR enrolled in the TransplantLines Biobank and Cohort Study. We included 689 SOTR (38.5% female, mean [±SD] age 58 [±14] years) at median [interquartile range] 3 [1-9] years after transplantation, of which 287 (41.7%) reported mild or severe tremor. In multinomial logistic regression analyses, whole blood tacrolimus trough concentration was an independent determinant of mild tremor (OR per µg/L increase: 1.11, 95% CI: 1.02 to 1.21, p = 0.019). Furthermore, in linear regression analyses, severe tremor was strongly and independently associated with lower physical and mental HRQoL (β = -16.10, 95% CI: -22.23 to -9.98, p < 0.001 and β = -12.68, 95% CI: -18.23 to -7.14, p < 0.001 resp.). SOTR frequently report tremor-related impairment of activities of daily living. Tacrolimus trough concentrations appeared as a main determinant of tremor among SOTR. The strong and independent association of tremor-related impairment with lower HRQoL warrants further studies into the effects of tacrolimus on tremor. Clinical Trial Registration: ClinicalTrials.gov, Identifier NCT03272841.

The yield of staging laparoscopy for resectable and borderline resectable pancreatic cancer in the PREOPANC randomized controlled trial

BACKGROUND

The necessity of the staging laparoscopy in patients with pancreatic cancer is still debated. The objective of this study was to assess the yield of staging laparoscopy for detecting occult metastases in patients with resectable or borderline resectable pancreatic cancer.

METHOD

This was a post-hoc analysis of the randomized controlled PREOPANC trial in which patients with resectable or borderline resectable pancreatic cancer were randomized between preoperative chemoradiotherapy or immediate surgery. Patients assigned to preoperative treatment underwent a staging laparoscopy prior to preoperative treatment according to protocol, to avoid unnecessary chemoradiotherapy in patients with occult metastatic disease.

RESULTS

Of the 246 included patients, 7 did not undergo surgery. A staging laparoscopy was performed in 133 patients (55.6%) and explorative laparotomy in 106 patients (44.4%). At staging laparoscopy, occult metastases were detected in 13 patients (9.8%); 12 liver metastases and 1 peritoneal metastasis. At direct explorative laparotomy, occult metastases were found in 9 patients (8.5%); 6 with liver metastases, 1 with peritoneal metastases, and 2 with metastases at multiple sites. One patient had peritoneal metastases at exploration after a negative staging laparoscopy. Patients with occult metastases were more likely to receive palliative chemotherapy if found with staging laparoscopy compared to laparotomy (76.9% vs. 30.0%, p = 0.040).

CONCLUSIONS

Staging laparoscopy detected occult metastases in about 10% of patients with resectable or borderline resectable pancreatic cancer. These patients were more likely to receive palliative systemic chemotherapy compared to patients in whom occult metastases were detected with laparotomy. A staging laparoscopy is recommended before planned resection.

Development of a set of patient reported outcome measures for patients with benign liver tumours and cysts: patient focus groups and systematic review

BACKGROUND

Patient reported outcome measures (PROMs) may be useful for patients with benign liver tumours and cysts (BLTC) to evaluate the impact of treatment and/or guide shared decision making. Yet, a set of PROMs relevant to patients with BLTC is currently unavailable. In this study, we selected a PROMs set for patients with BLTC.

METHODS

Potentially relevant patient reported outcomes (PROs) were selected by psychologist-researchers based on keywords used or suggested by participants of two virtual focus groups meetings consisting of thirteen female BLTC patients with a median age of 50 years. Subsequently, patients were asked to report their most relevant PROs. PROMs identified by systematic literature review and computerized adaptive tests (CATs) in the Patient-Reported Outcomes Measurement Information System (PROMIS) were considered in selecting the final PROMs set to assess relevant outcomes.

RESULTS

The most important PROs were: insecurity/anxiety (11/12 patients), pain (9/12 patients), fatigue (8/12 patients), and limitations in daily life (5/12 patients). The literature review included 23 studies, which used various generic and disease-specific PROMs, often not measuring (all) relevant PROs. The final selected PROMs set included numerical rating scales for pain, two questions on overall health and quality of life and four PROMIS CATs.

CONCLUSIONS

A PROMs set generically and efficiently measuring outcomes relevant for patients with BLTC was developed and may be used in future research and clinical practice.

Short- and Long-Term Outcomes of Pancreatic Cancer Resection in Elderly Patients: A Nationwide Analysis

BACKGROUND

The number of elderly patients with pancreatic cancer is growing, however clinical data on the short-term outcomes, rate of adjuvant chemotherapy, and survival in these patients are limited and we therefore performed a nationwide analysis.

METHODS

Data from the prospective Dutch Pancreatic Cancer Audit were analyzed, including all patients undergoing pancreatic cancer resection between January 2014 and December 2016. Patients were classified into two age groups: <75 and ≥75 years. Major complications (Clavien-Dindo grade 3 or higher), 90-day mortality, rates of adjuvant chemotherapy, and survival were compared between age groups. Factors associated with start of adjuvant chemotherapy and survival were evaluated with logistic regression and multivariable Cox regression analysis.

RESULTS

Of 836 patients, 198 were aged ≥75 years (24%) and 638 were aged <75 years (76%). Median follow-up was 38 months (interquartile range [IQR] 31-47). Major complications (31% vs. 28%; p = 0.43) and 90-day mortality (8% vs. 5%; p = 0.18) did not differ. Adjuvant chemotherapy was started in 37% of patients aged ≥75 years versus 69% of patients aged <75 years (p < 0.001). Median overall survival (OS) was 15 months (95% confidence interval [CI] 14-18) versus 21 months (95% CI 19-24; p < 0.001). Age ≥75 years was not independently associated with OS (hazard ratio 0.96, 95% CI 0.79-1.17; p = 0.71), but was associated with a lower rate of adjuvant chemotherapy (odds ratio 0.27, 95% CI 0.18-0.40; p < 0.001).

CONCLUSIONS

The rate of major complications and 90-day mortality after pancreatic resection did not differ between elderly and younger patients; however, elderly patients were less often treated with adjuvant chemotherapy and their OS was shorter.

Normothermic liver machine perfusion as a dynamic platform for regenerative purposes: What does the future have in store for us?

Liver transplantation has become an immense success; nevertheless, far more recipients are registered on waiting lists than there are available donor livers for transplantation. High-risk, extended criteria donor livers are increasingly used to reduce the discrepancy between organ demand and supply. Especially for high-risk livers, dynamic preservation using machine perfusion can decrease post-transplantation complications and may increase donor liver utilisation by improving graft quality and enabling viability testing before transplantation. To further increase the availability of donor livers suitable for transplantation, new strategies are required that make it possible to use organs that are initially too damaged to be transplanted. With the current progress in experimental liver transplantation research, (long-term) normothermic machine perfusion may be used in the future as a dynamic platform for regenerative medicine approaches, enabling repair and regeneration of injured donor livers. Currently explored therapeutics such as defatting cocktails, RNA interference, senolytics, and stem cell therapy may assist in the repair and/or regeneration of injured livers before transplantation. This review will provide a forecast of the future utility of normothermic machine perfusion in decreasing the imbalance between donor liver demand and supply by enabling the repair and regeneration of damaged donor livers.

Nationwide Validation of the 8th American Joint Committee on Cancer TNM Staging System and Five Proposed Modifications for Resected Pancreatic Cancer

BACKGROUND

The prognostic value of four proposed modifications to the 8th American Joint Committee on Cancer (AJCC) TNM staging system has yet to be evaluated. This study aimed to validate five proposed modifications.

METHODS

Patients who underwent pancreatic ductal adenocarcinoma resection (2014-2016), as registered in the prospective Dutch Pancreatic Cancer Audit, were included. Stratification and prognostication of TNM staging systems were assessed using Kaplan-Meier curves, Cox proportional hazard analyses, and C-indices. A new modification was composed based on overall survival (OS).

RESULTS

Overall, 750 patients with a median OS of 18 months (interquartile range 10-32) were included. The 8th edition had an increased discriminative ability compared with the 7th edition {C-index 0.59 (95% confidence interval [CI] 0.56-0.61) vs. 0.56 (95% CI 0.54-0.58)}. Although the 8th edition showed a stepwise decrease in OS with increasing stage, no differences could be demonstrated between all substages; stage IIA vs. IB (hazard ratio [HR] 1.30, 95% CI 0.80-2.09; p  = 0.29) and stage IIB vs. IIA (HR 1.17, 95% CI 0.75-1.83; p  = 0.48). The four modifications showed comparable prognostic accuracy (C-index 0.59-0.60); however, OS did not differ between all modified TNM stages (ns). The new modification, migrating T3N1 patients to stage III, showed a C-index of 0.59, but did detect significant survival differences between all TNM stages (p  < 0.05).

CONCLUSIONS

The 8th TNM staging system still lacks prognostic value for some categories of patients, which was not clearly improved by four previously proposed modifications. The modification suggested in this study allows for better prognostication in patients with all stages of disease.

Treatment and overall survival of four types of non-metastatic periampullary cancer: nationwide population-based cohort study

BACKGROUND

Periampullary adenocarcinoma consists of pancreatic adenocarcinoma (PDAC), distal cholangiocarcinoma (DC), ampullary cancer (AC), and duodenal adenocarcinoma (DA). The aim of this study was to assess treatment modalities and overall survival by tumor origin.

METHODS

Patients diagnosed with non-metastatic periampullary cancer in 2012-2018 were identified from the Netherlands Cancer Registry. OS was studied with Kaplan-Meier analysis and multivariable Cox regression analyses, stratified by origin.

RESULTS

Among the 8758 patients included, 68% had PDAC, 13% DC, 12% AC, and 7% DA. Resection was performed in 35% of PDAC, 56% of DC, 70% of AC, and 59% of DA. Neoadjuvant and/or adjuvant therapy was administered in 22% of PDAC, 7% of DC, 7% of AC, and 12% of DA. Three-year OS was highest for AC (37%) and DA (34%), followed by DC (21%) and PDAC (11%). Adjuvant therapy was associated with improved OS among PDAC (HR = 0.62; 95% CI 0.55-0.69) and DC (HR = 0.69; 95% CI 0.48-0.98), but not AC (HR = 0.87; 95% CI 0.62-1.22) and DA (HR = 0.85; 95% CI 0.48-1.50).

CONCLUSION

This retrospective study identified considerable differences in treatment modalities and OS between the four periampullary cancer origins in daily clinical practice. An improved OS after adjuvant chemotherapy could not be demonstrated in patients with AC and DA.

Gut microbiome dysbiosis is associated with increased mortality after solid organ transplantation

Organ transplantation is a life-saving treatment for patients with end-stage disease, but survival rates after transplantation vary considerably. There is now increasing evidence that the gut microbiome is linked to the survival of patients undergoing hematopoietic cell transplant, yet little is known about the role of the gut microbiome in solid organ transplantation. We analyzed 1370 fecal samples from 415 liver and 672 renal transplant recipients using shotgun metagenomic sequencing to assess microbial taxonomy, metabolic pathways, antibiotic resistance genes, and virulence factors. To quantify taxonomic and metabolic dysbiosis, we also analyzed 1183 age-, sex-, and body mass index-matched controls from the same population. In addition, a subset of 78 renal transplant recipients was followed longitudinally from pretransplantation to 24 months after transplantation. Our data showed that both liver and kidney transplant recipients suffered from gut dysbiosis, including lower microbial diversity, increased abundance of unhealthy microbial species, decreased abundance of important metabolic pathways, and increased prevalence and diversity of antibiotic resistance genes and virulence factors. These changes were found to persist up to 20 years after transplantation. Last, we demonstrated that the use of immunosuppressive drugs was associated with the observed dysbiosis and that the extent of dysbiosis was associated with increased mortality after transplantation. This study represents a step toward potential microbiome-targeted interventions that might influence the outcomes of recipients of solid organ transplantation.

The Impact of Donor and Recipient Genetic Variation on Outcomes After Solid Organ Transplantation: A Scoping Review and Future Perspectives

At the outset of solid organ transplantation, genetic variation between donors and recipients was recognized as a major player in mechanisms such as allograft tolerance and rejection. Genome-wide association studies have been very successful in identifying novel variant-trait associations, but have been difficult to perform in the field of solid organ transplantation due to complex covariates, era effects, and poor statistical power for detecting donor-recipient interactions. To overcome a lack of statistical power, consortia such as the International Genetics and Translational Research in Transplantation Network have been established. Studies have focused on the consequences of genetic dissimilarities between donors and recipients and have reported associations between polymorphisms in candidate genes or their regulatory regions with transplantation outcomes. However, knowledge on the exact influence of genetic variation is limited due to a lack of comprehensive characterization and harmonization of recipients' or donors' phenotypes and validation using an experimental approach. Causal research in genetics has evolved from agnostic discovery in genome-wide association studies to functional annotation and clarification of underlying molecular mechanisms in translational studies. In this overview, we summarize how the recent advances and progresses in the field of genetics and genomics have improved the understanding of outcomes after solid organ transplantation.

Prolonged preservation by hypothermic machine perfusion facilitates logistics in liver transplantation: A European observational cohort study

A short period (1-2 h) of hypothermic oxygenated machine perfusion (HOPE) after static cold storage is safe and reduces ischemia-reperfusion injury-related complications after liver transplantation. Machine perfusion time is occasionally prolonged for logistical reasons, but it is unknown if prolonged HOPE is safe and compromises outcomes. We conducted a multicenter, observational cohort study of patients transplanted with a liver preserved by prolonged (≥4 h) HOPE. Postoperative biochemistry, complications, and survival were evaluated. The cohort included 93 recipients from 12 European transplant centers between 2014-2021. The most common reason to prolong HOPE was the lack of an available operating room to start the transplant procedure. Grafts underwent HOPE for a median (range) of 4:42 h (4:00-8:35 h) with a total preservation time of 10:50 h (5:50-20:50 h). Postoperative peak ALT was 675 IU/L (interquartile range 419-1378 IU/L). The incidence of postoperative complications was low, and 1-year graft and patient survival were 94% and 88%, respectively. To conclude, good outcomes are achieved after transplantation of donor livers preserved with prolonged (median 4:42 h) HOPE, leading to a total preservation time of almost 21 h. These results suggest that simple, end-ischemic HOPE may be utilized for safe extension of the preservation time to ease transplantation logistics.