Liver specification of human iPSC-derived endothelial cells transplanted into mouse liver.

Background & Aims: Liver sinusoidal endothelial cells (LSECs) are important in liver development, regeneration, and pathophysiology, but the differentiation process underlying their tissue-specific phenotype is poorly understood and difficult to study because primary human cells are scarce. The aim of this study was to use human induced pluripotent stem cell (hiPSC)-derived LSEC-like cells to investigate the differentiation process of LSECs. Methods: hiPSC-derived endothelial cells (iECs) were transplanted into the livers of Fah-/-/Rag2-/-/Il2rg-/- mice and assessed over a 12-week period. Lineage tracing, immunofluorescence, flow cytometry, plasma human factor VIII measurement, and bulk and single cell transcriptomic analysis were used to assess the molecular and functional changes that occurred following transplantation. Results: Progressive and long-term repopulation of the liver vasculature occurred as iECs expanded along the sinusoids between hepatocytes and increasingly produced human factor VIII, indicating differentiation into LSEC-like cells. To chart the developmental profile associated with LSEC specification, the bulk transcriptomes of transplanted cells between 1 and 12 weeks after transplantation were compared against primary human adult LSECs. This demonstrated a chronological increase in LSEC markers, LSEC differentiation pathways, and zonation. Bulk transcriptome analysis suggested that the transcription factors NOTCH1, GATA4, and FOS have a central role in LSEC specification, interacting with a network of 27 transcription factors. Novel markers associated with this process included EMCN and CLEC14A. Additionally, single cell transcriptomic analysis demonstrated that transplanted iECs at 4 weeks contained zonal subpopulations with a region-specific phenotype. Conclusions: Collectively, this study confirms that hiPSCs can adopt LSEC-like features and provides insight into LSEC specification. This humanised xenograft system can be applied to further interrogate LSEC developmental biology and pathophysiology, bypassing current logistical obstacles associated with primary human LSECs. Impact and implications: Liver sinusoidal endothelial cells (LSECs) are important cells for liver biology, but better model systems are required to study them. We present a pluripotent stem cell xenografting model that produces human LSEC-like cells. A detailed and longitudinal transcriptomic analysis of the development of LSEC-like cells is included, which will guide future studies to interrogate LSEC biology and produce LSEC-like cells that could be used for regenerative medicine.

Endoscopic management of ingested toothpick resulting in duodeno-ureteric fistula.

Toothpicks are commonly used but rarely ingested. Unlike most foreign bodies, if accidentally swallowed these rarely spontaneously pass. The duodenum has been reported as the most common site of toothpick foreign body lodgement in the upper gastrointestinal tract. We report the case of a 57-year-old presenting with recurrent urosepsis after non recognition of a toothpick impaction in the duodenum with fistulisation into the right renal pelvis. Endoscopic removal of the foreign body was successful in management of the urosepsis.

Recurrence and outcomes of non-functional pancreatic neuroendocrine tumours post-resection: an Australian retrospective, multicentre cohort study.

INTRODUCTION: Pancreatic neuroendocrine tumours (PNETs) are heterogenous entities with variable clinical outlook. The prevalence of PNETs is increasing in Australia. Despite this, data on peri-operative management and post-operative prognosis for Australian patients is scant in the literature. METHODS: Patients from two tertiary hospitals in Victoria were recruited. Inclusion criteria included patients who underwent curative surgical resection for primary, non-functioning, PNETs without metastases from January 2011 to December 2021. Patients were identified via histopathological reports, CMBS and ICD-10 codes. Data were sourced from Electronic Medical Records, outpatient notes and letters. RESULTS: Sixty-three patients (34 Male, 29 Female) underwent surgical resection for PNETs. Fifty-three patients (84.1%) had a post-operative complication, and 21 (33.3%) had severe complications. Two patients had disease recurrence. Head PNETs had higher Ki-67% (5.33 vs. 2.72, P = 0.29), and likelihood of nodal spread (9 (36%) vs. 4 (16%), P = 0.054). Pancreatic Head resections were also associated with more frequent ICU admissions (21 (84%) vs. 18 (54.5), P = 0.024), longer ICU stays (4.05 vs. 2.17 days, P = 0.10) and hospital stays (26.76 vs. 8.27 days, P = <0.001). CONCLUSION: Within the limitations of this study, it demonstrates that surgical resection of PNET carries a significant morbidity with a low rate of recurrence. Additionally, Pancreatic head NETs may be associated with higher grades and increased likelihood of nodal metastases. Considering this, careful patient selection is paramount.

The incidence of symptomatic remnant gall bladder: a population study.

BACKGROUND: Subtotal cholecystectomy is utilized in conditions of high risk to critical structures, like the common bile duct. However, the remnant gall bladder may become symptomatic and require a completion cholecystectomy for treatment. This second procedure can itself be a risk to critical structures. To establish the incidence of redo-cholecystectomy and identify risk factors that lead to subtotal cholecystectomy and repeat operation in a review of state-based practices for cholecystectomy. METHODS: A search of state coding records relating to cholecystectomy from 1998 to 2016. Patients who were coded for cholecystectomy-related procedures on different dates were identified. Patients who underwent the procedures within 6 months were excluded to avoid acute post-operative complications and gall bladder malignancy. RESULTS: 210 719 cholecystectomies were performed. 1133 required repeat procedure. 616 were excluded, leaving 516 (0.25%) cholecystectomy patients requiring a second cholecystectomy. The subsequent operation was more likely to be an emergency procedure; involve transcystic bile duct exploration, adhesiolysis and require intensive care unit admission post-operatively. A repeat cholecystectomy was more likely to occur after having the primary procedure at a public hospital and when an intra-operative cholangiogram was not performed. Over the study period, the rate of repeat cholecystectomy increased from 0.02% to 0.6%. Incidentally, the rate of intra-operative cholangiogram during a primary cholecystectomy increased from 43% to 73%. CONCLUSIONS: Repeat cholecystectomy is an uncommon procedure. A second cholecystectomy is a more complex and likely to require intensive care unit support. Referral to a tertiary hepatobiliary unit is recommended.

Systematic review of liver directed therapy for uveal melanoma hepatic metastases.

BACKGROUND: Uveal melanoma (UM) is a rare malignancy with a propensity for metastasis to the liver. Systemic chemotherapy is typically ineffective in these patients with liver metastases and overall survival is poor. There are no evidence-based guidelines for management of UM liver metastases. The aim of this study was to review the evidence for management of UM liver metastases. METHODS: A systematic review of English literature publications was conducted across Ovid Medline, Ovid MEDLINE and Cochrane CENTRAL databases until April 2019. The primary outcome was overall survival, with disease free survival as a secondary outcome. RESULTS: 55 studies were included in the study, with 2446 patients treated overall. The majority of these studies were retrospective, with 17 of 55 including comparative data. Treatment modalities included surgery, isolated hepatic perfusion (IHP), hepatic artery infusion (HAI), transarterial chemoembolization (TACE), selective internal radiotherapy (SIRT) and Immunoembolization (IE). Survival varied greatly between treatments and between studies using the same treatments. Both surgery and liver-directed treatments were shown to have benefit in selected patients. CONCLUSION: Predominantly retrospective and uncontrolled studies suggest that surgery and locoregional techniques may prolong survival. Substantial variability in patient selection and study design makes comparison of data and formulation of recommendations challenging.

Safety, efficacy and compliance of extended thromboprophylaxis in hepatobiliary and upper gastrointestinal surgery.

BACKGROUND: Extended venothromboprophylaxis (eVTP) after abdominal surgery for hepatobiliary (HPB) and upper gastrointestinal (UGI) malignancies is recommended. Safety, efficacy and compliance within this group of surgical patients are not well described. The primary aim was to assess safety and compliance of post-operative administration of eVTP with low molecular weight heparin. Secondary aim was to assess barriers to treatment and monitor the rate of post-operative venous thromboembolism. METHODS: A prospective observational cohort study of patients undergoing abdominal surgery for HPB or UGI malignancies was undertaken from January 2014 to June 2016. All patients were assessed for eVTP. Demographics, clinical outcomes and clinical questionnaires on discharge and at follow-up 6 weeks post their initial surgery were used to assess the safety, compliance and efficacy of eVTP. RESULTS: A total of 100 patients were assessed for post-operative eVTP. Of these, 80 patients were prescribed 28 days of low molecular weight heparin. Of 80 patients, 65 (85%) patients completed the full eVTP, 11 (13%) missed 1-5 injections and only four (6%) missed 6-15 injections. In the 80 eVTP patients, there were no episodes of significant bleeding or venous thromboembolism. A total of nine (11%) patients would be unwilling to undertake eVTP again for a variety of reasons, including ease of disposal of syringes and needle phobias. CONCLUSION: The administration of eVTP in patients undergoing major HPB and UGI surgery is safe, with minimal morbidity and high compliance. The greatest barrier to administration is doctor prescription.

Endoscopic sphincterotomy with sphincteroplasty for the management of choledocholithiasis: a single-centre experience.

BACKGROUND: Balloon dilatation of the ampulla at endoscopic retrograde cholangiopancreatography (ERCP) is increasingly utilized in the management of large bile duct stones. The aim of this study was to review and compare the outcomes of using endoscopic sphincterotomy with endoscopic balloon dilatation (sphincteroplasty) in a combined approach as a single-stage (immediate) or a two-stage procedure (delayed). METHODS: A retrospective review of medical records for all patients undergoing ERCP and balloon dilatation for choledocholithiasis between January 2010 and December 2012 was undertaken. Outcomes measured included patient demographics, stone size, degree of dilatation performed, success of stone extraction, number of procedures required for duct clearance and procedure-related complications. RESULTS: One hundred and thirty-six ERCPs were performed with balloon sphincteroplasty. One hundred and four had a previous sphincterotomy with a delayed balloon dilatation and 32 had sphincterotomy with immediate dilatation. The overall clearance rate of the common bile duct for immediate and delayed groups was 93% (28/30) and 93% (81/87), respectively. Bile duct clearance after the first procedure was achieved in 70% (21/30) of patients in the immediate group and 74% (64/87) in the delayed group. There were six complications in the delayed group and four in the immediate group. The most frequently used balloon size was 10 mm for both groups with mean sizes of 10.34 (2.93) and 11.73 (2.87) in the immediate and delayed groups, respectively. CONCLUSION: Our study suggests that use of a combined approach is safe and effective and may provide benefits over using endoscopic balloon dilatation or endoscopic sphincterotomy alone in the treatment of choledocholithiasis.

The developing clinical problem of chemotherapy-induced hepatic injury.

Chemotherapy is being administered to an increasing number of patients with colorectal liver metastases (CRLM), whether they have resectable disease or not. Although this may be appropriate to downstage patients with unresectable disease, and offers theoretical advantages to those who have resectable disease, there is a price to be paid in the development of chemotherapy-induced hepatic injuries (CIHI). These include chemotherapy-associated fatty liver diseases and sinusoidal injuries. The main chemotherapeutic agents currently used in the adjuvant setting for colorectal carcinoma, and the neoadjuvant treatment of CRLM include 5-flurouracil, oxaliplatin and irinotecan, and while there are non-specific and overlapping injury profiles, oxaliplatin does appear to be primarily associated with sinusoidal injury and irinotecan with steatohepatitis. In this review, the rationale for administering chemotherapy to patients with CRLM is presented, and the problems this brings are outlined. The specific injury patterns will be detailed, as well as the data correlating specific chemotherapy regimens to these injury patterns. Finally, the clinical outcomes of patients with CRLM who undergo neoadjuvant chemotherapy followed by hepatic resection will be considered. The need for methods to identify patients at risk of CIHI and to recognize established CIHI prior to surgery will be emphasized.

Correlations between histopathological diagnosis of chemotherapy-induced hepatic injury, clinical features, and perioperative morbidity.

BACKGROUND: Chemotherapy has in some series been linked with increased morbidity after a hepatectomy. Hepatic injuries may result from the treatment with chemotherapy, but can also be secondary to co-morbid diseases. The aim of the present study was to draw correlations between clinical features, treatment with chemotherapy and injury phenotypes and assess the impact of each upon perioperative morbidity. PATIENTS AND METHODS: Retrospective samples (n= 232) were scored grading steatosis, steatohepatitis and sinusoidal injury (SI). Clinical data were retrieved from medical records. Correlations were drawn between injury, clinical features and perioperative morbidity. RESULTS: Injury rates were 18%, 4% and 19% for steatosis, steatohepatitis and SI, respectively. High-grade steatosis was more common in patients with diabetes [odds ratio (OR) = 3.33, P= 0.01] and patients with a higher weight (OR/kg = 1.04, P= 0.02). Steatohepatitis was increased with metabolic syndrome (OR = 5.88, P= 0.02). Chemotherapy overall demonstrated a trend towards an approximately doubled risk of high-grade steatosis and steatohepatitis although not affecting SI. However, pre-operative chemotherapy was associated with an increased SI (OR = 2.18, P= 0.05). Operative morbidity was not increased with chemotherapy, but was increased with steatosis (OR = 2.38, P= 0.02). CONCLUSIONS: Diabetes and higher weight significantly increased the risk of steatosis, whereas metabolic syndrome significantly increased risk of steatohepatitis. The presence of high-grade steatosis increases perioperative morbidity, not administration of chemotherapy per se.

mRNA gene expression correlates with histologically diagnosed chemotherapy-induced hepatic injury.

INTRODUCTION: Chemotherapy-induced hepatic injuries (CIHI) are an increasing problem facing hepatic surgeons. It may be possible to predict the risk of developing CIHI by analysis of genes involved in the metabolism of chemotherapeutics, previously established as associated with other forms of toxicity. METHODS: Quantitative reverse transcriptase-polymerase chain reaction methodology (q-RT-PCR) was employed to quantify mRNA expression of nucleotide excision repair genes ERCC1 and ERCC2, relevant in the neutralization of damage induced by oxaliplatin, and genes encoding enzymes relevant to 5-flurouracil metabolism, [thymidylate synthase (TS), thymidine phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD)] in 233 hepatic resection samples. mRNA expression was correlated with a histopathological injury scored via previously validated methods in relation to steatosis, steatohepatitis and sinusoidal obstruction syndrome. RESULTS: Low-level DPD mRNA expression was associated with steatosis [odds ratio (OR) = 3.95, 95% confidence interval (CI) = 1.53-10.19, P < 0.003], especially when stratified by just those patients exposed to chemotherapy (OR = 4.48, 95% CI = 1.31-15.30 P < 0.02). Low expression of ERCC2 was associated with sinusoidal injury (P < 0.001). There were no further associations between injury patterns and target genes investigated. CONCLUSIONS: Predisposition to the development of CIHI may be predictable based upon individual patient expression of genes encoding enzymes related to the metabolism of chemotherapeutics.

Endoscopic management of post-cholecystectomy biliary fistula.

OBJECTIVE: Bile duct injury is an uncommon but potentially serious complication in cholecystectomy. A recognized treatment for minor biliary injury is internal biliary decompression by endoscopic retrograde cholangiopancreatography (ERCP) and stent insertion. The aim of this study was to assess the effectiveness of ERCP in the management of minor biliary injuries. METHODS: A retrospective review of medical records at a tertiary referral centre identified 36 patients treated for postoperative minor biliary injuries between 2006 and 2010. Management involved establishing a controlled biliary fistula followed by ERCP to confirm the nature of the injury and decompress the bile duct with stent insertion. RESULTS: Controlled biliary fistulae were established in all 36 patients. Resolution of the bile leak was achieved prior to ERCP in seven patients, and ERCP with stent insertion was successful in 27 of the remaining 29 patients. Resolution of the bile leak was achieved in all patients without further intervention. The median time to resolution after successful ERCP was 4 days. Two patients underwent ERCP complicated by mild pancreatitis. No other complications were seen. CONCLUSIONS: This review confirms that postoperative minor biliary injuries can be managed by sepsis control and semi-urgent endoscopic biliary decompression.

Post-hepatectomy haemorrhage: a definition and grading by the International Study Group of Liver Surgery (ISGLS).

BACKGROUND: A standardized definition of post-hepatectomy haemorrhage (PHH) has not yet been established. METHODS: An international study group of hepatobiliary surgeons from high-volume centres was convened and a definition of PHH was developed together with a grading of severity considering the impact on patients' clinical management. RESULTS: The definition of PHH varies strongly within the hepatic surgery literature. PHH is defined as a drop in haemoglobin level > 3 g/dl post-operatively compared with the post-operative baseline level and/or any post-operative transfusion of packed red blood cells (PRBC) for a falling haemoglobin and/or the need for radiological intervention (such as embolization) and/or re-laparotomy to stop bleeding. Evidence of intra-abdominal bleeding should be obtained by imaging or blood loss via the abdominal drains if present. Transfusion of up to two units of PRBC is considered as being Grade A PHH. Grade B PHH requires transfusion of more than two units of PRBC, whereas the need for invasive re-intervention such as embolization and/ or re-laparotomy defines Grade C PHH. CONCLUSION: The proposed definition and grading of severity of PHH enables valid comparisons of results from different studies. It is easily applicable in clinical routine and should be applied in future trials to standardize reporting of complications.

Bile leakage after hepatobiliary and pancreatic surgery: a definition and grading of severity by the International Study Group of Liver Surgery.

BACKGROUND: Despite the potentially severe impact of bile leakage on patients' perioperative and long-term outcome, a commonly used definition of this complication after hepatobiliary and pancreatic operations has not yet been established. The aim of the present article is to propose a uniform definition and severity grading of bile leakage after hepatobiliary and pancreatic operative therapy. METHODS: An international study group of hepatobiliary and pancreatic surgeons was convened. A consensus definition of bile leakage after hepatobiliary and pancreatic operative therapy was developed based on the postoperative course of bilirubin concentrations in patients' serum and drain fluid. RESULTS: After evaluation of the postoperative course of bilirubin levels in the drain fluid of patients who underwent hepatobiliary and pancreatic operations, bile leakage was defined as bilirubin concentration in the drain fluid at least 3 times the serum bilirubin concentration on or after postoperative day 3 or as the need for radiologic or operative intervention resulting from biliary collections or bile peritonitis. Using this criterion severity of bile leakage was classified according to its impact on patients' clinical management. Grade A bile leakage causes no change in patients' clinical management. A Grade B bile leakage requires active therapeutic intervention but is manageable without relaparotomy, whereas in Grade C, bile leakage relaparotomy is required. CONCLUSION: We propose a simple definition and severity grading of bile leakage after hepatobiliary and pancreatic operative therapy. The application of the present proposal will enable a standardized comparison of the results of different clinical trials and may facilitate an objective evaluation of diagnostic and therapeutic modalities in the field of hepatobiliary and pancreatic operative therapy.

Posthepatectomy liver failure: a definition and grading by the International Study Group of Liver Surgery (ISGLS).

BACKGROUND: Posthepatectomy liver failure is a feared complication after hepatic resection and a major cause of perioperative mortality. There is currently no standardized definition of posthepatectomy liver failure that allows valid comparison of results from different studies and institutions. The aim of the current article was to propose a definition and grading of severity of posthepatectomy liver failure. METHODS: A literature search on posthepatectomy liver failure after hepatic resection was conducted. Based on the normal course of biochemical liver function tests after hepatic resection, a simple and easily applicable definition of posthepatectomy liver failure was developed by the International Study Group of Liver Surgery. Furthermore, a grading of severity is proposed based on the impact on patients' clinical management. RESULTS: No uniform definition of posthepatectomy liver failure has been established in the literature addressing hepatic surgery. Considering the normal postoperative course of serum bilirubin concentration and International Normalized Ratio, we propose defining posthepatectomy liver failure as the impaired ability of the liver to maintain its synthetic, excretory, and detoxifying functions, which are characterized by an increased international normalized ratio and concomitant hyperbilirubinemia (according to the normal limits of the local laboratory) on or after postoperative day 5. The severity of posthepatectomy liver failure should be graded based on its impact on clinical management. Grade A posthepatectomy liver failure requires no change of the patient's clinical management. The clinical management of patients with grade B posthepatectomy liver failure deviates from the regular course but does not require invasive therapy. The need for invasive treatment defines grade C posthepatectomy liver failure. CONCLUSION: The current definition of posthepatectomy liver failure is simple and easily applicable in clinical routine. This definition can be used in future studies to allow objective and accurate comparisons of operative interventions in the field of hepatic surgery.

Endoscopic management of recurrent primary bile duct stones.

BACKGROUND: The management of recurrent choledocholithiasis today remains as challenging as in the pre-endoscopic era. Between 2 and 7% of affected patients have historically required surgical intervention for the treatment of recurrent or retained choledocholithiasis and of these, as many as 24% develop biliary complications. To avoid surgery, repeated endoscopic management of the problem has been suggested. In this study, we evaluate our policy of repeated endoscopic management of recurrent primary bile duct stones. METHODS: This study examined a cohort of nine patients identified from a prospective database with recurrent choledocholithiasis. Demographic, clinical and investigative details were recorded and data were analysed. Complications were determined from a review of the patient's file. RESULTS: There were nine patients and 66 procedures were carried out. Mean age at time of first endoscopy was 70.1 years (36-91 years). Three patients were of male sex (33.3%). The mean number of endoscopies carried out per patient was 7.3 (3-13). Failure to completely clear the duct occurred in 36.4% of all endoscopies. There were no periprocedural complications. CONCLUSION: Repeated endoscopic stone extraction by endoscopic retrograde cholangiopancreatography when required is a safe policy. However, this technique will only provide temporary relief from primary duct stones and repeated endoscopic treatment, again safe, will be required.