International consensus guidelines on robotic pancreatic surgery in 2023.

Background: With the rapid development of robotic surgery, especially for the abdominal surgery, robotic pancreatic surgery (RPS) has been applied increasingly around the world. However, evidence-based guidelines regarding its application, safety, and efficacy are still lacking. To harvest robust evidence and comprehensive clinical practice, this study aims to develop international guidelines on the use of RPS. Methods: World Health Organization (WHO) Handbook for Guideline Development, GRADE Grid method, Delphi vote, and the AGREE-II instrument were used to establish the Guideline Steering Group, Guideline Development Group, and Guideline Secretary Group, formulate 19 clinical questions, develop the recommendations, and draft the guidelines. Three online meetings were held on 04/12/2020, 30/11/2021, and 25/01/2022 to vote on the recommendations and get advice and suggestions from all involved experts. All the experts focusing on minimally invasive surgery from America, Europe and Oceania made great contributions to this consensus guideline. Results: After a systematic literature review 176 studies were included, 19 questions were addressed and 14 recommendations were developed through the expert assessment and comprehensive judgment of the quality and credibility of the evidence. Conclusions: The international RPS guidelines can guide current practice for surgeons, patients, medical societies, hospital administrators, and related social communities. Further randomized trials are required to determine the added value of RPS as compared to open and laparoscopic surgery.

International experts consensus guidelines on robotic liver resection in 2023.

The robotic liver resection (RLR) has been increasingly applied in recent years and its benefits shown in some aspects owing to the technical advancement of robotic surgical system, however, controversies still exist. Based on the foundation of the previous consensus statement, this new consensus document aimed to update clinical recommendations and provide guidance to improve the outcomes of RLR clinical practice. The guideline steering group and guideline expert group were formed by 29 international experts of liver surgery and evidence-based medicine (EBM). Relevant literature was reviewed and analyzed by the evidence evaluation group. According to the WHO Handbook for Guideline Development, the Guidance Principles of Development and Amendment of the Guidelines for Clinical Diagnosis and Treatment in China 2022, a total of 14 recommendations were generated. Among them were 8 recommendations formulated by the GRADE method, and the remaining 6 recommendations were formulated based on literature review and experts' opinion due to insufficient EBM results. This international experts consensus guideline offered guidance for the safe and effective clinical practice and the research direction of RLR in future.

Early vs late drain removal after pancreatic resection-a systematic review and meta-analysis.

BACKGROUND: Reducing clinically relevant post-operative pancreatic fistula (CR-POPF) incidence after pancreatic resections has been a topic of great academic interest. Optimizing post-operative drain management is a potential strategy in reducing this major complication. METHODS: Studies involving pancreatic resections, including both pancreaticoduodenectomy (PD) and distal pancreatic resections (DP), with intra-operative drain placement were screened. Early drain removal was defined as removal before or on the 3rd post-operative day (POD) while late drain removal was defined as after the 3rd POD. The primary outcome was CR-POPF, International Study Group of Pancreatic Surgery (ISGPS) Grade B and above. Secondary outcomes were all complications, severe complications, post-operative haemorrhage, intra-abdominal infections, delayed gastric emptying, reoperation, length of stay, readmission, and mortality. RESULTS: Nine studies met the inclusion criteria and were included for analysis. The studies had a total of 8574 patients, comprising 1946 in the early removal group and 6628 in the late removal group. Early drain removal was associated with a significantly lower risk of CR-POPF (OR: 0.24, p < 0.01). Significant reduction in risk of post-operative haemorrhage (OR: 0.55, p < 0.01), intra-abdominal infection (OR: 0.35, p < 0.01), re-admission (OR: 0.63, p < 0.01), re-operation (OR: 0.70, p = 0.03), presence of any complications (OR: 0.46, p < 0.01), and reduced length of stay (SMD: -0.75, p < 0.01) in the early removal group was also observed. CONCLUSION: Early drain removal is associated with significant reductions in incidence of CR-POPF and other post-operative complications. Further prospective randomised trials in this area are recommended to validate these findings.

Retained stone retrieval basket causing chronic pancreatitis: a case report.

Background: Endoscopic retrograde cholangiopancreatography is a common procedure performed for choledocholithiasis and gallstone pancreatitis. Although a relatively low risk procedure, it is not without its complications. Cases of impacted Dormia baskets during stone retrieval have been reported, but these are usually retrieved surgically during the same setting. Case summary: A 40-year-old man presented to our hospital with an episode of epigastric pain and discomfort. He has a prior background of recurrent episodes of pancreatitis of which he underwent prior endoscopic therapy in his home country. Initial investigations revealed a metallic object seen on abdominal x-ray, computer tomographic scan of the abdomen and pelvis, and magnetic resonance imaging of the pancreas. Further evaluation was done with endoscopy, which revealed a retained stone extraction basket from a previous endoscopic retrograde pancreatography, resulting in recurrent episodes of acute chronic pancreatitis. Although the retained foreign body was removed, he subsequently developed further complications of portal vein thrombosis as a result of recurrent acute chronic pancreatitis, which required anticoagulation. Conclusion: This case highlights the importance of retrieving any foreign body from the pancreas, especially on the head, to prevent the development of further complications.

A genomic enhancer signature associates with hepatocellular carcinoma prognosis.

Background & Aims: Lifestyle and environmental-related exposures are important risk factors for hepatocellular carcinoma (HCC), suggesting that epigenetic dysregulation significantly underpins HCC. We profiled 30 surgically resected tumours and the matched adjacent normal tissues to understand the aberrant epigenetic events associated with HCC. Methods: We identified tumour differential enhancers and the associated genes by analysing H3K27 acetylation (H3K27ac) chromatin immunoprecipitation sequencing (ChIP-seq) and Hi-C/HiChIP data from the resected tumour samples of 30 patients with early-stage HCC. This epigenome dataset was analysed with previously reported genome and transcriptome data of the overlapping group of patients from the same cohort. We performed patient-specific differential expression testing using multiregion sequencing data to identify genes that undergo both enhancer and gene expression changes. Based on the genes selected, we identified two patient groups and performed a recurrence-free survival analysis. Results: We observed large-scale changes in the enhancer distribution between HCC tumours and the adjacent normal samples. Many of the gain-in-tumour enhancers showed corresponding upregulation of the associated genes and vice versa, but much of the enhancer and gene expression changes were patient-specific. A subset of the upregulated genes was activated in a subgroup of patients' tumours. Recurrence-free survival analysis revealed that the patients with a more robust upregulation of those genes showed a worse prognosis. Conclusions: We report the genomic enhancer signature associated with differential prognosis in HCC. Findings that cohere with oncofoetal reprogramming in HCC were underpinned by genome-wide enhancer rewiring. Our results present the epigenetic changes in HCC that offer the rational selection of epigenetic-driven gene targets for therapeutic intervention or disease prognostication in HCC. Impact and Implications: Lifestyle and environmental-related exposures are the important risk factors of hepatocellular carcinoma (HCC), suggesting that tumour-associated epigenetic dysregulations may significantly underpin HCC. We profiled tumour tissues and their matched normal from 30 patients with early-stage HCC to study the dysregulated epigenetic changes associated with HCC. By also analysing the patients' RNA-seq and clinical data, we found the signature genes - with epigenetic and transcriptomic dysregulation - associated with worse prognosis. Our findings suggest that systemic approaches are needed to consider the surrounding cellular environmental and epigenetic changes in HCC tumours.

Safely Implementing a Program of Pure Laparoscopic Donor Right Hepatectomy: The Experience From a Southeast Asian Center.

Laparoscopic donor right hepatectomy (LDRH) is a technically challenging procedure. There is increasing evidence demonstrating the safety of LDRH in high-volume expert centers. We report our center's experience in implementing an LDRH program in a small- to medium-sized transplantation program. Methods: Our center systematically introduced a laparoscopic hepatectomy program in 2006. We started with minor wedge resections followed by major hepatectomies with increasing complexities. In 2017, we performed our first laparoscopic living donor left lateral sectionectomy. Since 2018, we have performed 8 cases of right lobe living donor hepatectomy (laparoscopy-assisted: 4 and pure laparoscopic: 4). Results: The median operative time was 418 (298-540) min, whereas the median blood loss was 300 (150-900) mL. Two patients (25%) had surgical drain placed intraoperatively. The median length of stay was 5 (3-8) d, and the median time to return to work was 55 (24-90) d. None of the donors sustained any long-term morbidity or mortality. Conclusions: Small- to medium-sized transplant programs face unique challenges in adopting LDRH. Progressive introduction of complex laparoscopic surgery, a mature living donor liver transplantation program, appropriate patient selection, and the invitation of an expert to proctor the LDRH are necessary to ensure success.

Multi-region sampling with paired sample sequencing analyses reveals sub-groups of patients with novel patient-specific dysregulation in Hepatocellular Carcinoma.

BACKGROUND: Conventional differential expression (DE) testing compares the grouped mean value of tumour samples to the grouped mean value of the normal samples, and may miss out dysregulated genes in small subgroup of patients. This is especially so for highly heterogeneous cancer like Hepatocellular Carcinoma (HCC). METHODS: Using multi-region sampled RNA-seq data of 90 patients, we performed patient-specific differential expression testing, together with the patients' matched adjacent normal samples. RESULTS: Comparing the results from conventional DE analysis and patient-specific DE analyses, we show that the conventional DE analysis omits some genes due to high inter-individual variability present in both tumour and normal tissues. Dysregulated genes shared in small subgroup of patients were useful in stratifying patients, and presented differential prognosis. We also showed that the target genes of some of the current targeted agents used in HCC exhibited highly individualistic dysregulation pattern, which may explain the poor response rate. DISCUSSION/CONCLUSION: Our results highlight the importance of identifying patient-specific DE genes, with its potential to provide clinically valuable insights into patient subgroups for applications in precision medicine.

IFNγ-IL-17+ CD8 T cells contribute to immunosuppression and tumor progression in human hepatocellular carcinoma.

IL-17-producing CD8 (Tc17) T cells have been shown to play an important role in infection and chronic inflammation, however their implications in hepatocellular carcinoma (HCC) remain elusive. In this study, we performed cytometry by time-of-flight (CyTOF) and revealed the distinctive immunological phenotypes of two IFNγ+ and IFNγ- Tc17 subsets that were preferentially enriched in human HCC. Single-cell RNA-sequencing analysis further revealed regulatory circuits governing the different phenotypes of these Tc17 subsets. In particular, we discovered that IFNγ- Tc17 subset demonstrated pro-tumoral characteristics and expressed higher levels of CCL20. This corresponded to increased tumor infiltration of T regulatory cells (Treg) validated by immunohistochemistry in another independent HCC cohort, demonstrating the immunosuppressive functions of IFNγ- Tc17 subset. Most importantly, higher intra-tumoral proportions of IFNγ- Tc17 were associated with poorer prognosis in patients with HCC and this was further validated in The Cancer Genome Atlas (TCGA) HCC cohort. Taken together, this compendium of transcriptomic and proteomic data of Tc17 subsets sheds light on the immunosuppressive phenotypes of IFNγ- Tc17 and its implications in HCC progression.

Locally invasive recurrence or metastasis of pheochromocytoma into the liver?-clinicopathological challenges.

Pheochromocytomas (PCC) are rare and functional neuroendocrine tumors developing from adrenal chromaffin cells. Predicting malignant behavior especially in the absence of metastasis can be quite challenging even in the era of improved understanding of the molecular mechanisms involved in PCCs. Currently, two histopathological grading systems Pheochromocytoma of the Adrenal Gland Scaled Score (PASS) and Grading of Adrenal Pheochromocytoma and Paraganglioma (GAPP) score are used in clinical practice, but these are subject to significant interobserver variability. Some of the most useful clinical factors associated with malignancy are large size ([4-5 cm), and genetic features such as presence of SDHB germline mutations. Local invasion is uncommon in PCC and metastasis seen in 10 to 17% but higher in germline mutations and when this occurs management can be challenging. Here, we report on a case with challenges faced by the pathologist and clinicians alike in diagnosis and management of PCC recurrence.

Impact of donor age on recipient morbidity and mortality after living donor liver transplantation.

BACKGROUND: Evidence for use of graft from older donors in living donor liver transplantation (LDLT) has been conflicting. This study aims to clarify the impact of donor age on recipient morbidity and mortality after adult LDLT. METHODS: A total of 90 live liver donors and recipients who underwent primary adult-to-adult LDLT were divided into three groups according to donor age: donors in 20s (D-20s) group, donors in 30s and 40s (D-30s and 40s) group and donors in 50s & 60s (D-50s and 60s) group. Multivariate analyses were conducted to look for independent risk/prognostic factors. Donor age was analysed as a continuous variable to determine an optimal cut off. RESULTS: Overall donor morbidity was 4/90 (4.44%), major donor morbidity was 1/90 (1.11%) and there was no donor mortality. Recipients in the D-20s group had better 1-, 3- and 5-year recipient survival than recipients in the D-50s and 60s group (96%, 91%, 91% versus 73%, 58%, 58%, respectively) (P = 0.020). Donor age was identified to be an independently significant risk factor for increased major complications (P = 0.007) and prognostic factor for reduced overall survival (P = 0.014). The optimal donor age cut off was determined to be 46.5 years old. CONCLUSION: Older donors are associated with poorer recipient outcomes after adult-to-adult LDLT. Usage of liver grafts from older donors should be carefully considered when choosing liver grafts for patients undergoing LDLT.

Pan-cancer pervasive upregulation of 3' UTR splicing drives tumourigenesis.

Most mammalian genes generate messenger RNAs with variable untranslated regions (UTRs) that are important post-transcriptional regulators. In cancer, shortening at 3' UTR ends via alternative polyadenylation can activate oncogenes. However, internal 3' UTR splicing remains poorly understood as splicing studies have traditionally focused on protein-coding alterations. Here we systematically map the pan-cancer landscape of 3' UTR splicing and present this in SpUR ( http://www.cbrc.kaust.edu.sa/spur/home/ ). 3' UTR splicing is widespread, upregulated in cancers, correlated with poor prognosis and more prevalent in oncogenes. We show that antisense oligonucleotide-mediated inhibition of 3' UTR splicing efficiently reduces oncogene expression and impedes tumour progression. Notably, CTNNB1 3' UTR splicing is the most consistently dysregulated event across cancers. We validate its upregulation in hepatocellular carcinoma and colon adenocarcinoma, and show that the spliced 3' UTR variant is the predominant contributor to its oncogenic functions. Overall, our study highlights the importance of 3' UTR splicing in cancer and may launch new avenues for RNA-based anti-cancer therapeutics.

Dynamic phenotypic heterogeneity and the evolution of multiple RNA subtypes in hepatocellular carcinoma: the PLANET study.

Intra-tumor heterogeneity (ITH) is a key challenge in cancer treatment, but previous studies have focused mainly on the genomic alterations without exploring phenotypic (transcriptomic and immune) heterogeneity. Using one of the largest prospective surgical cohorts for hepatocellular carcinoma (HCC) with multi-region sampling, we sequenced whole genomes and paired transcriptomes from 67 HCC patients (331 samples). We found that while genomic ITH was rather constant across stages, phenotypic ITH had a very different trajectory and quickly diversified in stage II patients. Most strikingly, 30% of patients were found to contain more than one transcriptomic subtype within a single tumor. Such phenotypic ITH was found to be much more informative in predicting patient survival than genomic ITH and explains the poor efficacy of single-target systemic therapies in HCC. Taken together, we not only revealed an unprecedentedly dynamic landscape of phenotypic heterogeneity in HCC, but also highlighted the importance of studying phenotypic evolution across cancer types.

Trajectory of immune evasion and cancer progression in hepatocellular carcinoma.

Immune evasion is key to cancer initiation and later at metastasis, but its dynamics at intermediate stages, where potential therapeutic interventions could be applied, is undefined. Here we show, using multi-dimensional analyses of resected tumours, their adjacent non-tumour tissues and peripheral blood, that extensive immune remodelling takes place in patients with stage I to III hepatocellular carcinoma (HCC). We demonstrate the depletion of anti-tumoural immune subsets and accumulation of immunosuppressive or exhausted subsets along with reduced tumour infiltration of CD8 T cells peaking at stage II tumours. Corresponding transcriptomic modification occur in the genes related to antigen presentation, immune responses, and chemotaxis. The progressive immune evasion is validated in a murine model of HCC. Our results show evidence of ongoing tumour-immune co-evolution during HCC progression and offer insights into potential interventions to reverse, prevent or limit the progression of the disease.

Hypoxia-driven immunosuppression by Treg and type-2 conventional dendritic cells in HCC.

BACKGROUND AND AIMS: Hypoxia is one of the central players in shaping the immune context of the tumor microenvironment (TME). However, the complex interplay between immune cell infiltrates within the hypoxic TME of HCC remains to be elucidated. APPROACH AND RESULTS: We analyzed the immune landscapes of hypoxia-low and hypoxia-high tumor regions using cytometry by time of light, immunohistochemistry, and transcriptomic analyses. The mechanisms of immunosuppression in immune subsets of interest were further explored using in vitro hypoxia assays. Regulatory T cells (Tregs) and a number of immunosuppressive myeloid subsets, including M2 macrophages and human leukocyte antigen-DR isotype (HLA-DRlo ) type 2 conventional dendritic cell (cDC2), were found to be significantly enriched in hypoxia-high tumor regions. On the other hand, the abundance of active granzyme Bhi PD-1lo CD8+ T cells in hypoxia-low tumor regions implied a relatively active immune landscape compared with hypoxia-high regions. The up-regulation of cancer-associated genes in the tumor tissues and immunosuppressive genes in the tumor-infiltrating leukocytes supported a highly pro-tumorigenic network in hypoxic HCC. Chemokine genes such as CCL20 (C-C motif chemokine ligand 20) and CXCL5 (C-X-C motif chemokine ligand 5) were associated with recruitment of both Tregs and HLA-DRlo cDC2 to hypoxia-high microenvironments. The interaction between Tregs and cDC2 under a hypoxic TME resulted in a loss of antigen-presenting HLA-DR on cDC2. CONCLUSIONS: We uncovered the unique immunosuppressive landscapes and identified key immune subsets enriched in hypoxic HCC. In particular, we identified a potential Treg-mediated immunosuppression through interaction with a cDC2 subset in HCC that could be exploited for immunotherapies.

Percutaneous transhepatic interventional therapy of portal vein stenosis in paediatric liver transplantation: A systematic review of efficacy and safety.

PURPOSE OF THE SYSTEMATIC REVIEW: To determine the efficacy and safety of percutaneous trans-hepatic balloon and/or stent angioplasty (PTA) in the management of portal vein (PV) stenosis following paediatric liver transplantation. METHODS: Articles were included from a systematic search of Medline, Embase, Cochrane CENTRAL, ClinicalTrials.gov and International Clinical Trials Registry from inception to the 29th of August 2020. RESULTS: There were 213 paediatric liver recipients who underwent PTA for PV stenosis in 19 included studies published between 1991 and 2019. Balloon angioplasty was the initial treatment in the majority (n = 153). Primary stent placement (n = 34) was performed for elastic recoil, intimal tears and PV kinks and rescue stent placement (n = 14) for recurrent PV stenosis following primary balloon angioplasty. The technical success was 97.6%-100% overall, 97.6%-100% for balloon-angioplasty-only and 100% for primary stenting. The clinical success was 50%-100% overall, 50%-100% for balloon-angioplasty-only and 100% for primary stenting. Long-term PV patency was 50%-100% overall, 37.5%-100% for balloon-angioplasty-only and 100% for primary stenting. Primary balloon angioplasty was successful in 78% of the cases. Of the recurrent PV stenoses, 9% resolved with stent placement and one required a meso-Rex shunt. There was one re-transplantation without stenting. The complication rate was 2.6% for balloon-angioplasty-only (bleeding, liver abscess, 2 PV thromboses) and 5.9% for primary stenting (bleeding, stent-fracture). There was no procedure-related mortality. CONCLUSION: Percutaneous transhepatic balloon angioplasty may be the initial management of portal vein stenosis in paediatric liver recipients. Stent placement may be a primary option in selected cases and a reliable rescue option for recurrent portal vein stenosis following balloon-angioplasty-only.

Living donor hepatectomy in medium volume liver transplant centre has comparable outcomes to high volume centres: validation of donabedian quality assurance framework.

BACKGROUND: Given the complexity of living donor hepatectomy, it is expected that high hospital volume will better outcomes. This study aims to evaluate post-operative outcomes for living donor hepatectomy in a medium volume liver transplant centre and compare to outcomes in high volume centres. Also, it serves as a validation tool for framework of structure-process-outcome model for safe living donor hepatectomy program. METHODS: 204 donors who underwent donor hepatectomy between June 1996 to September 2019 were reviewed retrospectively and compared to outcomes in high volume centres. RESULTS: At 6 months, overall donor morbidity rate was 20/204 (9.8%). Wound complications were most common at 5/204 (2.5%). Majority of complications were either Clavien grade 1 or 2 and only 3 donors had Clavien grade 3 complications. There was zero donor mortality. DISCUSSION: Our centre's donor morbidity rate of 9.8% is the one of the lowest reported in the published literature. With increased experience, stringent donor selection and enhanced perioperative care by a multi-disciplinary team, outcomes in a medium volume centre can match the outcomes reported in high volume centres. The framework for quality in terms of structure, process and outcomes is presented which can be adopted for developing programs.

Meta-analysis and systematic review: Prevalence, graft failure, mortality, and post-operative thrombosis in liver transplant recipients with pre-operative portal vein thrombosis.

AIMS: This study seeks to evaluate the association between pre-transplant portal vein thrombosis (PVT) and overall survival, graft failure, waitlist mortality, and post-operative PVT after liver transplantation. METHODS: A conventional pairwise meta-analysis between patients with and without pre-transplant PVT was conducted using hazard ratios or odds ratios where appropriate. RESULTS: Prevalence of preoperative PVT was 11.6% (CI 9.70-13.7%). Pre-operative PVT was associated with increased overall mortality (HR 1.45, 95% CI 1.27-1.65) and graft loss (HR 1.58, 95% CI 1.34-1.85). In particular, grade 3 (HR 1.59, 95% CI 1.00-2.51) and 4 (HR 2.24, 95% CI 1.45-3.45) PVT significantly increased mortality, but not grade 1 or 2 PVT. Patients with PVT receiving living donor (HR 1.54, 95% CI 1.24-1.91) and deceased donor (HR 1.52, 95% CI 1.21-1.92) liver transplantation had increased mortality, with no significant difference between transplant types (P = .13). Furthermore, pre-transplant PVT was associated with higher occurrence of post-transplant PVT (OR 5.06, 95% CI 3.89-6.57). Waitlist mortality was not significantly increased in patients with pre-transplant PVT. CONCLUSION: Graft failure, mortality, and post-operative PVT are more common in pre-transplant PVT patients, especially in grade 3 or 4 PVT. Prophylactic anticoagulation can be considered to reduce re-thrombosis and improve survival.

Evaluation of Adult Living Donor Liver Transplantation in Largest Southeast Asian Transplantation Center: Benchmarking With Adult-to-Adult Living Donor Liver Transplantation (A2ALL) Experience.

BACKGROUND: The volume-outcome relation for complex surgical procedures such as living donor liver transplantation (LDLT) generally favors high volume (HV) centers. It is important for low to medium volume (MV) centers to evaluate their centers' performance against HV centers to allow early detection and correction of potential systemic issues. There is a dearth of national and international comprehensive registries for LDLT that may allow reasonable risk-adjusted comparisons for benchmarking. This study aims to evaluate the LDLT program by comparing our center's performance against HV centers of the Adult-to-Adult Living Donor Liver Transplantation cohort. STUDY DESIGN: Patient outcomes from a MV transplant center were compared with 11 HV transplant centers from the Adult-to-Adult Living Donor Liver Transplantation cohort. Outcomes evaluated included length of hospital stay, same admission mortality, 90-day mortality, and overall survival. RESULTS: A total of 1381 patients were analzyed. HV 1 to 4, 6, 8, 9, and 11 centers had a shorter median length of hospital stay compared with the MV center (All Dunnett corrected P values all less than .05). HV 9 and 11 centers had lower same admission mortality compared with the MV center (Dunnett corrected P = .023 and .015). After adjusting for other significant predictors, the MV center had comparable 90-day mortality rates and overall survival rates to all HV centers. CONCLUSION: This benchmarking exercise has demonstrated that the limitation of low institutional case volume can be overcome with a protocol-based framework to implement a safe LDLT program. This framework presented can be adopted for developing programs.