Thyroid Hormone Levels Correlate With the Maturation of Implanted Pancreatic Endoderm Cells in Patients With Type 1 Diabetes.

BACKGROUND: Macroencapsulated pancreatic endoderm cells (PECs) can reverse diabetes in rodents and preclinical studies revealed that thyroid hormones in vitro and in vivo bias PECs to differentiate into insulin-producing cells. In an ongoing clinical trial, PECs implanted in macroencapsulation devices into patients with type 1 diabetes were safe but yielded heterogeneous outcomes. Though most patients developed meal responsive C-peptide, levels were heterogeneous and explanted grafts had variable numbers of surviving cells with variable distribution of endocrine cells. METHODS: We measured circulating triiodothyronine and thyroxine levels in all patients treated at 1 of the 7 sites of the ongoing clinical trial and determined if thyroid hormone levels were associated with the C-peptide or glucagon levels and cell fate of implanted PECs. RESULTS: Both triiodothyronine and thyroxine levels were significantly associated with the proportion of cells that adopted an insulin-producing fate with a mature phenotype. Thyroid hormone levels were inversely correlated to circulating glucagon levels after implantation, suggesting that thyroid hormones lead PECs to favor an insulin-producing fate over a glucagon-producing fate. In mice, hyperthyroidism led to more rapid maturation of PECs into insulin-producing cells similar in phenotype to PECs in euthyroid mice. CONCLUSION: These data highlight the relevance of thyroid hormones in the context of PEC therapy in patients with type 1 diabetes and suggest that a thyroid hormone adjuvant therapy may optimize cell outcomes in some PEC recipients.

Outcomes of liver transplant recipients with high MELD scores: an experience from a Canadian centre.

BACKGROUND: The frequency with which patients with high Model for End-Stage Liver Disease (MELD) scores undergo liver transplantation has been increasing. Canadian literature regarding the outcomes of liver transplantation in recipients with high MELD scores is limited. The primary objective of this study was to assess patient and graft survival among recipients with high (> 35) and low (≤ 35) MELD scores. Secondary objectives were to potentially identify independent predictors of graft failure and patient mortality. METHODS: We conducted a retrospective chart review of patients undergoing liver transplantation at a single Canadian centre from 2012 to 2017. RESULTS: A total of 332 patients were included in the study: 280 patients had a MELD score of 35 or lower, and 52 had a MELD score above 35. Patients with high MELD scores had higher rates of pretransplant acute kidney injury and dialysis (p < 0.001), admission to the intensive care unit (ICU) or intubation (p < 0.001), intraoperative blood product transfusions (p < 0.001) and post-transplantation acute kidney injury and dialysis (p < 0.001), as well as longer ICU (p < 0.001) and hospital stays (p = 0.002). One- and 3-year patient survival in recipients with MELD scores of 35 or lower was 93.1% and 84.9% versus 85.0% and 80.0% in recipients with MELD scores above 35 (p = 0.37). One- and 3-year graft survival in recipients with MELD scores of 35 or lower was 91.7% and 90.9% versus 77.2% and 72.8% in recipients with MELD scores above 35 (p < 0.001). Prior liver transplant was an independent predictor of patient mortality, and no independent predictors of graft failure were identified. When MELD was replaced with D-MELD (donor age × recipient MELD), it predicted graft failure but not patient survival. CONCLUSION: No difference in patient mortality was found between MELD groups. Graft survival was significantly lower in recipients with MELD scores above 35. D-MELD may potentially be used as an adjunct in determining risk of graft failure in recipients with high MELD scores.

Implanted pluripotent stem-cell-derived pancreatic endoderm cells secrete glucose-responsive C-peptide in patients with type 1 diabetes.

An open-label, first-in-human phase 1/2 study is being conducted to evaluate the safety and efficacy of pancreatic endoderm cells (PECs) implanted in non-immunoprotective macroencapsulation devices for the treatment of type 1 diabetes. We report an analysis on 1 year of data from the first cohort of 15 patients from a single trial site that received subcutaneous implantation of cell products combined with an immunosuppressive regimen. Implants were well tolerated with no teratoma formation or severe graft-related adverse events. After implantation, patients had increased fasting C-peptide levels and increased glucose-responsive C-peptide levels and developed mixed meal-stimulated C-peptide secretion. There were immunosuppression-related transient increases in circulating regulatory T cells, PD1high T cells, and IL17A+CD4+ T cells. Explanted grafts contained cells with a mature ß cell phenotype that were immunoreactive for insulin, islet amyloid polypeptide, and MAFA. These data, and associated findings (Shapiro et al., 2021), are the first reported evidence of meal-regulated insulin secretion by differentiated stem cells in patients.

The role of intraperitoneal chemotherapy in the surgical management of pancreatic ductal adenocarcinoma: a systematic review.

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with poor prognosis, particularly for patients with metastatic disease. Treatment for oligometastatic presentation has been reported in recent literature, but the role of intraperitoneal chemotherapy for patients with peritoneal metastases (PM) remains unclear. We performed a systematic literature search of the PubMed, Cochrane and Embase databases in order to identify clinical trials and case-series reporting on the safety and efficacy of intraperitoneal chemotherapy in patients with PDAC-derived PM. Eight publications reporting on 85 patients were identified, using three different therapeutic strategies. First, 37 patients received cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) for PDAC with PM. Grade 3 and 4 complications occurred in 37.8% of patients, without perioperative mortality. Median disease-free survival and overall survival (OS) rates varied from 4 to 36 months and 4 to 62 months, respectively. Secondly, 40 patients with resectable PDAC without PM received prophylactic HIPEC following pancreatic resection, with postoperative morbidity and mortality rates of 30% and 5%, and 5-year OS rates of 23-24%. Finally, eight patients with PDAC-derived peritoneal disease were converted to resectable disease after receiving neoadjuvant intraperitoneal chemotherapy and operated on with curative intent, achieving a median OS of 27.8 months. In conclusion, CRS with HIPEC for PDAC-derived PM appears to be safe, conferring the same postoperative morbidity and mortality as reported on non-pancreatic malignancies. In highly selected patients, it could be considered for short-term disease control. However, long-term survival remains poor. The addition of prophylactic HIPEC for resectable PDAC cannot be recommended.

Pancreatic Gastrinoma, Gastrointestinal Stromal Tumor (GIST), Pheochromocytoma, and Hürthle Cell Neoplasm in a Patient with Neurofibromatosis Type 1: A Case Report and Literature Review.

BACKGROUND Neurofibromatosis type 1 (NF1) is a multi-tumor syndrome in which affected patients develop malignancies that are rare in the overall population, such as tumors of neural or endocrine origin. CASE REPORT A 67-year-old woman with a clinical diagnosis of NF1 presented with abdominal pain and pneumoperitoneum. She underwent small-bowel resections for a perforated jejunal lesion and a second lesion in the ileum; pathology showed a neurofibroma at the site of the perforation and a 1-cm low-grade GIST, respectively. Additional staging with cross-sectional imaging identified a 3.7-cm pancreatic head mass and a 1.7-cm left adrenal mass; biochemical studies revealed elevated serum gastrin and urinary free metanephrines and catecholamines consistent with pheochromocytoma. Initial surgical management was a left posterior retroperitoneoscopic adrenalectomy. Postoperatively, gallium-68-DOTATOC PET/CT showed uptake in the pancreatic head and a 28-mm left thyroid nodule. Months later, she had an open pancreaticoduodenectomy. Pathology showed pheochromocytoma and a low-grade (G1) gastrinoma involving 2/8 peripancreatic lymph nodes (pT3pN1M0), respectively. Fine-needle aspiration biopsy of the thyroid nodule showed features consistent with a Hürthle cell neoplasm. Genetic testing identified a pathogenic mutation in NF1 and no mutations in BRCA1/2, CDC72, MEN1, or PALB2. The patient continues surveillance, with no evidence of recurrent disease. CONCLUSIONS We report the fifth case of gastrinoma associated with NF1 and the first to arise from the pancreas. This case of a pancreatic neuroendocrine tumor was associated with multiple additional neoplasms. Neuroendocrine tumors found in NF1 should raise suspicion of other malignancies.

Burden of hereditary cancer susceptibility in unselected patients with pancreatic ductal adenocarcinoma referred for germline screening.

BACKGROUND: Recent guidelines recommend consideration of germline testing for all newly diagnosed pancreatic ductal adenocarcinoma (PDAC). The primary aim of this study was to determine the burden of hereditary cancer susceptibility in PDAC. A secondary aim was to compare genetic testing uptake rates across different modes of genetic counselling. PATIENTS AND METHODS: All patients diagnosed with PDAC in the province of British Columbia, Canada referred to a population-based hereditary cancer program were eligible for multi-gene panel testing, irrespective of cancer family history. Any healthcare provider or patients themselves could refer. RESULTS: A total of 305 patients with PDAC were referred between July 2016 and January 2019. Two hundred thirty-five patients attended a consultation and 177 completed index germline genetic testing. 25/177 (14.1%) of unrelated patients had a pathogenic variant (PV); 19/25 PV were in known PDAC susceptibility genes with cancer screening or risk-reduction implications. PDAC was significantly associated with PV in ATM (OR, 7.73; 95% CI, 3.10 to 19.33, P = 6.14E-05) when comparing age and gender and ethnicity-matched controls tested on the same platform. The overall uptake rate for index testing was 59.2% and was significantly higher with 1-on-1 consultations and group consultations compared to telehealth consultations (88.9% vs 82.9% vs 61.8%, P < .001). CONCLUSION: In a prospective clinic-based cohort of patients with PDAC referred for testing irrespective of family history, germline PV were detected in 14.1%. PV in ATM accounted for half of all PVs and were significantly associated with PDAC. These findings support recent guidelines and will guide future service planning in this population.

The role of multiorgan procurement for abdominal transplant in general surgery resident education.

BACKGROUND: To assess the impact of participation of multiorgan procurement (MP) by general surgery (GS) residents on surgical knowledge and skills, a prospective cohort study of GS residents during transplant surgery rotation was performed. METHODS: Before and after participation in MPs, assessment of knowledge was performed by written pre and post tests and surgical skills by modified Objective Structured Assessment of Technical Skill (OSATS) score. Thirty-nine residents performed 84 MPs. RESULTS: Significant improvement was noted in the written test scores (63.3% vs 76.7%; P < 0.001). Better surgical score was associated with female gender (15.4 vs 13.3, P = <0.01), prior MP experience (16.2 vs 13.7, P = 0.03), and senior level resident (15.1 vs 13.0, P = 0.03). Supraceliac aortic dissection (P = 0.0017) and instrument handling (P = 0.041) improved with more MP operations. CONCLUSIONS: Participation in MP improves residents' knowledge of abdominal anatomy and surgical technique.

Living donor liver transplantation in the USA.

Living donor liver transplant (LDLT) accounts for a small volume of the transplants in the USA. Due to the current liver allocation system based on the model for end-stage liver disease (MELD), LDLT has a unique role in providing life-saving transplantation for patients with low MELD scores and significant complications from portal hypertension, as well as select patients with hepatocellular carcinoma (HCC). Donor safety is paramount and has been a topic of much discussion in the transplant community as well as the general media. The donor risk appears to be low overall, with a favorable long-term quality of life. The latest trend has been a gradual shift from right-lobe grafts to left-lobe grafts to reduce donor risk, provided that the left lobe can provide adequate liver volume for the recipient.

Inferior vena cava reconstruction for leiomyosarcoma of Zone I-III requiring complete hepatectomy and bilateral nephrectomy with autotransplantation.

The inferior vena cava (IVC) is the most common site of leiomyosarcomas arising from a vascular origin. Leiomyosarcomas of the IVC are categorized by anatomical location. Zone I refers to the infrarenal portion of the IVC, Zone II from the hepatic veins to the renal veins, and Zone III from the right atrium to the hepatic veins. This is a rare presentation of a Zone I-III leiomyosarcoma. Fifty-two-years-old female with a medical history significant only for HTN was admitted to the hospital with bilateral lower extremity edema and dyspnea. Two-dimensional echo demonstrated a right atrial thrombus, extending into the IVC. On subsequent CT and MRI, a 15 cm mass was noted that began in the right atrium and extended into the IVC, with continuation below the renal veins to above the level of the confluence of the common iliac veins. The patient underwent a complete resection of the mass, replacement of the IVC with Dacron graft, total hepatectomy and bilateral nephrectomy, with liver and kidney autotransplantation. Pathology was consistent with a high grade spindle cell sarcoma of vena cava origin. Patient was readmitted approximately 4 weeks postoperatively to begin adjuvant chemotherapy. This case represents a zone I-III IVC leiomyosarcoma treated with surgical R0 resection. This included a hepatectomy, bilateral nephrectomy, and hepatic and left renal autotransplantation. These complex tumors should be treated with surgical resection, and require a multidisciplinary approach.

Improved long-term outcomes after resection of pancreatic adenocarcinoma: a comparison between two time periods.

BACKGROUND: Despite reduced perioperative mortality and routine use of adjuvant therapy following pancreatectomy for pancreatic ductal adenocarcinoma (PDAC), improvement in long-term outcome has been difficult to ascertain. This study compares outcomes in patients undergoing resection for PDAC within a single, high-volume academic institution over two sequential time periods. METHODS: Retrospective review of patients with resected PDAC, in two cohorts: period 1 (P1), 1991-2000; and period 2 (P2), 2001-2010. Univariate and multivariate analyses using the Cox proportional hazards model were performed to determine prognostic factors associated with long-term survival. Survival was evaluated using Kaplan-Meier analyses. RESULTS: A total of 179 pancreatectomies were performed during P1 and 310 during P2. Perioperative mortality was 6.7 % (12/179) in P1 and 1.6 % (5/310) in P2 (p = 0.003). P2 had a greater number of lymph nodes resected (17 [0-50] vs. 7 [0-31]; p < 0.001), and a higher lymph node positivity rate (69 % [215/310] vs. 58 % [104/179]; p = 0.021) compared with P1. The adjuvant therapy rate was 30 % (53/179) in P1 and 63 % (195/310) in P2 (p < 0.001). By multivariate analysis, node and margin status, tumor grade, adjuvant therapy, and time period of resection were independently associated with overall survival (OS) for both time periods. Median OS was 16 months (95 % confidence interval [CI] 14-20) in P1 and 27 months (95 % CI 24-30) in P2 (p < 0.001). CONCLUSIONS: Factors associated with improved long-term survival remain comparable over time. Short- and long-term survival for patients with resected PDAC has improved over time due to decreased perioperative mortality and increased use of adjuvant therapy, although the proportion of 5-year survivors remains small.

Posttransplant lymphoproliferative disorder presenting as a small bowel obstruction in a patient with pancreas transplantation alone.

Posttransplant lymphoproliferative disorder (PTLD) is a well-known complication associated with the transplant recipient. We chronicle a case of PTLD in a failed graft presenting as a small bowel obstruction in a pancreas-only transplant patient. While typical symptoms may be elusive in the complex immunosuppressed patient, graft pain along with persistent graft pancreatitis and a positive Epstein-Barr viremia should raise suspicion for an underlying PTLD.

Impact of viral hepatitis on outcomes after liver resection for hepatocellular carcinoma: results from a north american center.

BACKGROUND: Hepatitis B (HBV) and hepatitis C (HCV) are well-recognized risk factors for hepatocellular carcinoma (HCC). The characteristics and clinical outcomes of HCC arising from these conditions may differ. This study was conducted to compare the outcomes of HCC associated with HBV and HCV after liver resection. METHODS: Of 386 liver resections for HCC performed between July 1992 and April 2011, 181 patients had HBV and 74 patients had HCV. Patients with HBV/HCV coinfections (n = 20), non-HBV/HCV etiology (n = 94), and postoperative death within 3 months (n = 17) were excluded. Patient, tumor characteristics, and perioperative and oncologic outcomes were compared between patients with HBV and HCV. RESULTS: The patients with HBV had better overall survival (OS) than patients with HCV (68 vs. 59 months, p = 0.03); however, there was no difference in recurrence-free survival (RFS) between the groups (44 vs. 45 months, p = 0.1). The factors predictive of OS based on multivariate analyses included: vascular invasion [p < 0.01, hazard ratio (HR) = 3.4], Child-Pugh Score (p < 0.01, HR = 4.8), and underlying liver disease (HCV vs HBV) (p = 0.01, HR = 1.9). Vascular invasion and tumor number (p < 0.01, HR = 2.3 and p < 0.01, HR = 2.1) were independent predictors of RFS. CONCLUSIONS: OS but not RFS after liver resection for HCC is better in patients with HBV than HCV. This survival advantage for HBV patients may be due to differences in tumor biology and outcomes after disease recurrence.

Combined pancreaticoduodenectomy and colon resection for locally advanced peri-ampullary tumours: analysis of peri-operative morbidity and mortality.

BACKGROUND: Combined pancreaticoduodenectomy (PD) and colonic resection may be necessary to achieve an R0 resection of peri-ampullary tumours. The aim of this study was to examine the morbidity and mortality associated with this procedure. METHODS: A retrospective cohort study was performed comparing 607 patients who underwent a standard pancreaticoduodenectomy (S-PD) to 28 patients who had a concomitant colon resection and PD (PD-colon) over a 10-year period at an academic centre. RESULTS: Patients in the PD-colon group were more likely to have received neoadjuvant chemotherapy ± radiation (3/28, 11% versus 14/607, 2%, P = 0.024). Operative time was also longer (530 versus 410 min, P < 0.001) and they were more likely to have had portal vein resections (9/28, 32% versus 76/607, 13%, P = 0.007). There was no difference in the intra-operative blood loss, length of stay, or overall complication rates. The PD-colon group had a higher rate of severe post-operative bleeding (4/28, 11% versus 8/607, 1%, P = 0.002). The post-operative mortality rates for the PD-colon and PD groups were 2/28 (7%) and 8/607 (1%), respectively (P = 0.068). CONCLUSIONS: PD-colon has an acceptable risk of peri-operative morbidity compared with S-PD in well-selected patients.

Aberrant right hepatic artery in pancreaticoduodenectomy for adenocarcinoma: impact on resectability and postoperative outcomes.

OBJECTIVES: An aberrant right hepatic artery (aRHA) may pose technical and oncologic challenges during pancreaticoduodenectomy (PD) for pancreatic adenocarcinoma (PA) as a result of its proximity to the head of the pancreas. The aim of this study was to assess the impact of an aRHA on resectability, and perioperative and oncologic outcomes after PD for PA. METHODS: An 11-year retrospective cohort study was conducted. A total of 289 patients with PA scheduled for PD with intent for resection were included in the study. RESULTS: Of 289 patients, 249 underwent PD and 40 were found to have unresectable tumours. Incidences of aRHA in the resectable (14.9%) and unresectable (7.5%) groups were similar (P = 0.2); the main reasons for aborting PD were not directly related to the presence of an aRHA. In patients who underwent resection, complications occurred more frequently in the standard PD group (41.5% versus 24.3%; P = 0.04), but there was no difference in rates of positive margin (R1) resection (10.8% versus 16.0%; P = 0.4) or median overall survival (17 months versus 23 months; P = 0.1) between patients with and without an aRHA. CONCLUSIONS: The presence of an aRHA in patients with PA does not affect resectability. In patients with resectable tumours, the presence of an aRHA does not increase morbidity or R1 resection rates and does not impact on overall survival.

Tumor biology and pre-transplant locoregional treatments determine outcomes in patients with T3 hepatocellular carcinoma undergoing liver transplantation.

Liver transplantation is the optimal treatment for patients with hepatocellular carcinoma (HCC) and cirrhosis. This study was conducted to determine the impact of pre-transplant locoregional therapy (LRT) on HCC and our institution's experience with expansion to United Network of Organ Sharing Region 4 T3 (R4T3) criteria. Two hundred and twenty-five patients with HCC (176 meeting Milan and 49 meeting R4T3 criteria) underwent liver transplantation from 2002 to 2008. Compared with the Milan criteria, HCCs in R4T3 criteria displayed less favorable biological features such as higher median alpha-fetoprotein level (21.9 vs. 8.5 ng/mL, p = 0.01), larger tumor size, larger tumor number, and higher incidence of microvascular invasion (22% vs. 5%, p = 0.002). As a result, patients meeting Milan criteria had better five-yr survival (79% vs. 69%, p = 0.03) and a trend toward lower HCC recurrence rates (5% vs. 13%, p = 0.05). Pre-transplant LRT did not affect post-transplant outcomes in patients meeting Milan criteria but did result in lower three-yr HCC recurrence (7% vs. 75%, p < 0.001) and better three-yr survival (p = 0.02) in patients meeting R4T3 criteria. Tumor biology and pre-transplant LRT are important factors that determine the post-transplant outcomes in patients with HCC who meet R4T3 criteria.

Differentiation of definitive endoderm from mouse embryonic stem cells.

Efficient production of definitive endoderm from embryonic stem (ES) cells opens doors to the possibilities of differentiation of endoderm-derived tissues such as the intestines, pancreas, and liver that could address the needs of people with chronic diseases involving these organs. The lessons learned from developmental biology have contributed significantly to in vitro differentiation of definitive endoderm. Gastrulation, a process that results in the production of all three embryonic germ cell layers, definitive endoderm, mesoderm, and ectoderm, is an important step in embryonic development. Gastrulation occurs as a result of the events that are orchestrated by the signaling pathways involving Nodal, FGF, Wnt, and BMP. Understanding these signaling pathways has led to the introduction of key ingredients such as Activin A, FGF, Wnt, and BMP to the differentiation protocols that have been able to produce definitive endoderm from ES cells. Efficient production of definitive endoderm needs to meet the specific criteria that include (a) increase in the production of markers of definitive endoderm such as Sox 17, FOXA2, GSC, and Mixl1; (b) decrease in the production of markers of primitive/visceral/parietal endoderm, Sox 7 and OCT4; and (c) decrease in the mesoderm markers (Brachyury, MEOX) and ectoderm markers (Sox1 and ZIC1).

Renal-sparing immunosuppressive protocol using OKT3 after liver transplantation: a 19-year single-institution experience.

Different renal-sparing immunosuppressive protocols have been used in liver transplantation. At our institution, muromonab-CD3 (OKT3) is used in patients with acute renal failure (ARF), along with a delay in starting a calcineurin inhibitor. This study was conducted to compare outcomes in liver transplant patients with ARF who received OKT3 and those who did not. From 1988 to 2007, ARF was present in 1685 of 2587 patients (65%). OKT3 was used in 109 patients (OKT3 group). The control group (1416 patients) received a low-dose calcineurin inhibitor. The OKT3 group was more critically ill. In spite of this, the OKT3 group patients who were on renal replacement therapy (RRT) achieved long-term survival similar to that of the control group on RRT. Among the patients who were not on RRT, the OKT3 group had a higher complete recovery rate, but this did not translate into improved long-term survival. Bacterial and fungal infections were more common in the OKT3 group; however, there was no increased risk of malignancy or death from hepatitis C recurrence. The use of OKT3 in patients with ARF allowed more critically ill patients on RRT to achieve survival rates similar to those of patients who did not receive OKT3.