Extending Indications for Islet Autotransplantation in Pancreatic Surgery

Outcome after total pancreatectomy with islet autotransplantation: A European single-center study

BACKGROUND AND AIMS

Chronic pancreatitis may cause intractable abdominal pain, with total pancreatectomy sometimes being the last resort. To mitigate the subsequent diabetes, total pancreatectomy can be followed by islet autotransplantation (TP-IAT). The primary aim of this study was to assess the outcomes in patients undergoing TP-IAT at Karolinska University Hospital with respect to safety, postoperative complications, and islet graft function. A secondary aim was to compare liver to skeletal muscle as autotransplantation sites.

METHODS

Single-center observational cohort study on patients undergoing TP-IAT. Islets were transplanted either into the liver or skeletal muscle. Data on baseline characteristics and pretransplantory conditions were collected. Outcome measures included mortality and major postoperative complications as well as the glycemic measures: insulin use, fasting C-peptide, and HbA1c.

RESULTS

Between 2004 and 2020, 24 patients underwent TP-IAT. Islets were transplanted into the liver in 9 patients and into skeletal muscle in 15 patients. There was no 90-day mortality, and major complications (Clavien-Dindo ⩾IIIa) occurred in 26.7%, all related to the procedure of total pancreatectomy. Fasting C-peptide could be detected postoperatively, with higher levels in patients receiving islet autotransplantation into the liver (p = 0.006). Insulin independence was not achieved, although insulin doses at last follow-up were significantly lower in patients receiving islet autotransplantation into the liver compared to skeletal muscle (p = 0.036).

CONCLUSION

TP-IAT is safe and associated with tolerable risk, the component of islet autotransplantation being seemingly harmless. Although islet grafts maintain some endocrine function, insulin independence should not be expected. Regarding islet autotransplantation sites, the liver seems superior to skeletal muscle.

CLINICAL TRIAL REGISTRATION

Not applicable.

Autologous Pancreatic Islet Cell Transplantation Following Pancreatectomy for Pancreas Diseases Other Than Chronic Pancreatitis: A 15-Y Study of the Milan Protocol

BACKGROUND

Pancreatogenic diabetes, a consequence of pancreatic tissue loss following pancreatectomy, poses a significant challenge for patients undergoing pancreatic surgery. Islet autotransplantation (IAT) offers a promising approach to prevent or alleviate pancreatogenic diabetes, but its application has been limited to individuals with painful chronic pancreatitis.

METHODS

This study presents a 15-y clinical experience with the Milan Protocol, which expands IAT after pancreatectomy to a broader spectrum of patients with malignant and nonmalignant pancreatic diseases. The analysis evaluates feasibility, efficacy, and safety of IAT. Modified Igls criteria validated through the arginine test and mixed meal tolerance tests were used to assess long-term metabolic outcomes.

RESULTS

Between November 2008 and June 2023, IAT procedures were performed on 114 of 147 candidates. IAT-related complications occurred in 19 of 114 patients (16.7%), with 5 being potentially serious. Patients exhibited sustained C-peptide secretion over the 10-y follow-up period, demonstrating a prevalence of optimal and good beta-cell function. Individuals who underwent partial pancreatectomy demonstrated superior metabolic outcomes, including sustained C-peptide secretion and a reduced risk of developing diabetes or insulin dependence compared with those who underwent total pancreatectomy. For patients who had total pancreatectomy, the quantity of infused islets and tissue volume were identified as critical factors influencing metabolic outcomes. An increased risk of recurrence or progression of baseline diseases was not observed in subjects with neoplasms.

CONCLUSIONS

These findings provide valuable insights into the benefits and applications of IAT as a therapeutic option for pancreatogenic diabetes after pancreatic surgery, expanding its potential beyond painful chronic pancreatitis.

Total Pancreatectomy With Islet Autotransplantation as an Alternative to High-risk Pancreatojejunostomy After Pancreaticoduodenectomy: A Prospective Randomized Trial

OBJECTIVE

To compare pancreaticoduodenectomy (PD) and total pancreatectomy (TP) with islet autotransplantation (IAT) in patients at high risk of postoperative pancreatic fistula (POPF).

BACKGROUND

Criteria to predict the risk of POPF occurrence after PD are available. However, even when a high risk of POPF is predicted, TP is not currently accepted as an alternative to PD, because of its severe consequences on glycaemic control. Combining IAT with TP may mitigate such consequences.

METHODS

Randomized, open-label, controlled, bicentric trial (NCT01346098). Candidates for PD at high-risk pancreatic anastomosis (ie, soft pancreas and duct diameter ≤3 mm) were randomly assigned (1:1) to undergo either PD or TP-IAT. The primary endpoint was the incidence of complications within 90 days after surgery.

RESULTS

Between 2010 and 2019, 61 patients were assigned to PD (n=31) or TP-IAT (n=30). In the intention-to-treat analysis, morbidity rate was 90·3% after PD and 60% after TP-IAT ( P =0.008). According to complications' severity, PD was associated with an increased risk of grade ≥2 [odds ratio (OR)=7.64 (95% CI: 1.35-43.3), P =0.022], while the OR for grade ≥3 complications was 2.82 (95% CI: 0.86-9.24, P =0.086). After TP-IAT, the postoperative stay was shorter [median: 10.5 vs 16.0 days; P <0.001). No differences were observed in disease-free survival, site of recurrence, disease-specific survival, and overall survival. TP-IAT was associated with a higher risk of diabetes [hazard ratio=9.1 (95% CI: 3.76-21.9), P <0.0001], but most patients maintained good metabolic control and showed sustained C-peptide production over time.

CONCLUSIONS

TP-IAT may become the standard treatment in candidates for PD, when a high risk of POPF is predicted.

Thoracoabdominal Aortic Replacement Together with Curative Oncological Surgery in Retroperitoneal and Spinal Tumours

Malignancies with an extended encasement or infiltration of the aorta were previously considered inoperable. This series demonstrates replacement and subsequent resection of the thoracoabdominal aorta and its large branches as an adjunct to curative radical retroperitoneal and spinal tumor resection. Five consecutive patients were enrolled between 2016 and 2020, suffering from cancer of unknown primary, pleomorphic carcinoma, chordoma, rhabdoid sarcoma, and endometrial cancer metastasis. Wide surgical resection was the only curative option for these patients. For vascular replacement, extracorporeal membrane oxygenation (ECMO) was used as a partial left-heart bypass. The early technical success rate was 100% for vascular procedures and all patients underwent complete radical tumour resection with negative margins. All patients required surgical revision (liquor leak, n = 2; hematoma, n = 3; bypass revision, n = 1; bleeding, n = 1; biliary leak, n = 1). During follow-up (average 47 months, range 22–70) primary patency rates of aortic reconstructions and arterial bypasses were 100%; no patient suffered from recurrent malignant disease. Thoracoabdominal aortic replacement with rerouting of visceral and renal vessels is feasible in oncologic patients. In highly selected young patients, major vascular surgery can push the limits of oncologic surgery further, allowing a curative approach even in extensive retroperitoneal and spinal malignancies.

Interventional Radiological Management and Prevention of Complications after Pancreatic Surgery: Drainage, Embolization and Islet Auto-Transplantation

Pancreatic surgery still remains burdened by high levels of morbidity and mortality with a relevant incidence of complications, even in high volume centers. This review highlights the interventional radiological management of complications after pancreatic surgery. The current literature regarding the percutaneous drainage of fluid collections due to pancreatic fistulas, percutaneous transhepatic biliary drainage due to biliary leaks and transcatheter embolization (or stent–graft) due to arterial bleeding is analyzed. Moreover, also, percutaneous intra-portal islet auto-transplantation for the prevention of pancreatogenic diabetes in case of extended pancreatic resection is also examined. Moreover, a topic not usually treated in other similar reviewsas percutaneous intra-portal islet auto-transplantation for the prevention of pancreatogenic diabetes in case of extended pancreatic resection is also one of our areas of focus. In islet auto-transplantation, the patient is simultaneously donor and recipient. Differently from islet allo-transplantation, it does not require immunosuppression, has no risk of rejection and is usually efficient with a small number of transplanted islets.

Total pancreatectomy with intraportal islet autotransplantation for pancreatic malignancies: a literature overview

INTRODUCTION

'Brittle Diabetes' (BD) is a life-threatening metabolic complication after total pancreatectomy (TP). More than 500 Intraportal islet autotransplantation (IAT) have been performed to prevent this complication, with almost 70% insulin independence after 3 years. Even when insulin independence was not achieved, IAT successfully prevented severe hypoglycemia. Currently, preliminary results for oncologic situations are promising, but their oncological outcomes are still a matter of debate.

AREAS COVERED

We performed a bibliographic research of the last 25 years of data. Articles published in English in peer-reviewed journals were retained. In France, auto- and allo-islet transplantation was recently recognized as a valuable treatment for BD by the national health authority. While accepted for benign diseases, the risk of tumor spreading after IAT in oncologic situations is a source of concern.

EXPERT OPINION

Preliminary results of IAT in oncological situations are very encouraging. So far, there is no evidence of tumor dissemination. In our opinion, to overcome BD TP with IAT for resectable pancreatic malignancies in patients with a higher risk of postoperative pancreatic fistula and extended pancreatic cancers can be safely performed. Diagnosis of malignancy should not be considered as an exclusion criterion for IAT.

Total pancreatectomy sequelae and quality of life: results of islet autotransplantation as a possible mitigation strategy

Total pancreatectomy (TP) is a procedure weighed down not only by postoperative morbidity and mortality but also by long-term effects as a consequence of endocrine and exocrine pancreatic insufficiency. While the latter is now managed quite effectively with pancreatic enzyme replacement therapy, the former remains a challenge. The diabetes resulting after TP, with the complete loss of endogenous insulin and contraregulatory hormones, is characterized by important glycemic variations and is, therefore, frequently referred to as "brittle diabetes". One method to reduce the impact of brittle diabetes in patients undergoing TP is the re-infusion of autologous pancreatic islets isolated from the resected pancreas. Indications to islet autotransplantation (IAT), originally described for patients undergoing TP for chronic pancreatitis, have since been extended to selected patients with other benign and malignant diseases of pancreas. This review recaps on the literature regarding long-term postoperative complications, their impact on quality of life after TP and the role of IAT.

Total Pancreatectomy with Autologous Islet Cell Transplantation-The Current Indications

Total pancreatectomy is a major complex surgical procedure involving removal of the whole pancreatic parenchyma and duodenum. It leads to lifelong pancreatic exocrine and endocrine insufficiency. The control of surgery-induced diabetes (type 3) requires insulin therapy. Total pancreatectomy with autologous islet transplantation (TPAIT) is performed in order to prevent postoperative diabetes and its serious complications. It is very important whether it is safe and beneficial for patients in terms of postoperative morbidity and mortality, and long-term results including quality of life. Small duct painful chronic pancreatitis (CP) is a primary indication for TPAIT, but currently the indications for this procedure have been extended. They also include hereditary/genetic pancreatitis (HGP), as well as less frequent indications such as benign/borderline pancreatic tumors (intraductal papillary neoplasms, neuroendocrine neoplasms) and “high-risk pancreatic stump”. The use of TPAIT in malignant pancreatic and peripancreatic neoplasms has been reported in the worldwide literature but currently is not a standard but rather a controversial management in these patients. In this review, history, technique, indications, and contraindications, as well as short-term and long-term results of TPAIT, including pediatric patients, are described.

Feasibility and safety of robotic-assisted total pancreatectomy: a pilot western series

This study was designed to demonstrate non-inferiority of robot-assisted total pancreatectomy (RATP) to open total pancreatectomy (OPT) based on an intention-to-treat analysis, having occurrence of severe post-operative complications (SPC) as primary study endpoint. The two groups were matched (2:1) by propensity scores. Assuming a rate of SPC of 22.5% (non-inferiority margin: 15%; α: 0.05; β: 0.20; power: 80%), a total of 25 patients were required per group. During the study period (October 2008–December 2019), 209 patients received a total pancreatectomy. After application of exclusion and inclusion criteria, matched groups were extracted from an overall cohort of 132 patients (OPT: 107; RATP: 25). Before matching, the two groups were different with respect to prevalence of cardiac disease (24.3% versus 4.0%; p = 0.03), presence of jaundice (45.8% versus 12.0%; p = 0.002), presence of a biliary drainage (23.4% versus 0; p  = 0.004), history of weight loss (28.0% versus 8.0%; p = 0.04), and vein involvement (55.1% versus 28.0%) (p = 0.03). After matching, the two groups (OTP: 50; RATP: 25) were well balanced. Regarding primary study endpoint, SPC developed in 13 patients (26.0%) after OTP and in 6 patients (24.0%) after RATP (p = 0.85). Regarding secondary study endpoints, RATP was associated with longer median operating times [475 (408.8–582.5) versus 585 min (525–637.5) p = 0.003]. After a median follow-up time of 23.7 months (10.4–71), overall survival time [22.6 (11.2–81.2) versus NA (27.3–NA) p = 0.006] and cancer-specific survival [22.6 (11.2–NA) versus NA (27.3–NA) p = 0.02] were improved in patients undergoing RATP. In carefully selected patients, robot-assisted total pancreatectomy is non-inferior to open total pancreatectomy regarding occurrence of severe post-operative complications.

What Is New with Total Pancreatectomy and Autologous Islet Cell Transplantation? Review of Current Progress in the Field

Patients with chronic pancreatitis have benefited from total pancreatectomy and autologous islet cell transplantation (TPAIT) since the 1970s. Over the past few decades, improvements have been made in surgical technique and perioperative management that have led to improved success of islet cell function, insulin independence and patient survival. This article focuses on recent updates and advances for the TPAIT procedure that continue to expand and innovate the impact on patients with debilitating disease.

Total pancreatectomy as alternative to pancreatico-jejunal anastomosis in patients with high fistula risk score: the choice of the fearful or of the wise?

PURPOSE

Patients with fistula risk score (FRS) ≥7 are at the highest risk of developing clinically relevant post-operative pancreatic fistula (CR-POPF). There is no agreement on the management of this subpopulation. The primary outcome of the study was the definition of the role of intraoperative completion pancreatectomy (ICP) in patients at high risk for CR-POPF, as an alternative to high-risk pancreaticoduodenectomy (PD).

METHODS

This is an observational study set in a single tertiary referral center. Patients scheduled for PD in our center between 2010 and 2019 with FRS ≥7 were included in the study. Data were prospectively collected.

RESULTS

A total of 738 patients were scheduled for between 2010 and 2019, and 62 had FRS ≥7. Thirty-five patients were managed with PD and pancreatico-jejunal anastomosis (group A), and 27 with ICP (group B). Overall complication rate was significantly higher in group A than group B (95 versus 59%; p=0.005) and there was a not significantly higher rate of major complications (Clavien-Dindo ≥3) (43 versus 26%; p=0.192). In group A, 49% of patients had a CR-POPF. Median post-operative length of stay was 15 days in group A and 12 in group B (p=0.043). Readmission was observed only in group A (26%). In multivariate analysis, PD was an independent predictive factor of major post-operative morbidity (RR 9.27; CI 1.74-49.31). No patients in either group suffered major adverse events related to endocrine and exocrine insufficiency.

CONCLUSION

In high-FRS patients, ICP has good short-term outcomes relative to PD without major long-term events related to endocrine and exocrine insufficiency. ICP could be considered as a feasible alternative in selected cases.

Islet autotransplantation improves glycemic control in patients undergoing elective distal pancreatectomy for benign inflammatory disease

Islet autotransplantation (IAT) is increasingly being performed to mitigate against the diabetic complications of pancreatic resection in patients with benign inflammatory pancreatic disorders; however, the glycemic benefit of IAT in patients undergoing partial pancreatic resection is not known. We aimed to determine whether IAT improved glycemic outcomes in patients undergoing distal pancreatectomy for benign inflammatory disease. We performed a multicenter, retrospective case-control study of patients who underwent distal pancreatic resection with IAT at two U S tertiary care centers. The primary outcome was the mean change in pre- vs post-operative HgA1c following transplant as well as the development of new post-operative diabetes. Nine patients requiring distal pancreatectomy for benign disease underwent IAT and were compared to 13 historical controls without IAT. Baseline characteristics were similar between groups. With a median follow-up of 22 months, those who received an IAT had a smaller increase in their pre- vs post-operative HgA1c (0.42 vs 2.83, P = .004), and one case patient (14.3%) vs three control patients (23.1%) developed new post-operative diabetes (P = .581). We conclude that patients undergoing distal pancreatic resection for benign inflammatory disease should be considered for IAT, as long-term glycemic outcomes appear to be improved in those undergoing transplant.

Impact of microbial contamination of the islet product during total pancreatectomy with islet autotransplantation

BACKGROUND

The combined use of interleukin-1β and tumor necrosis factor-α blockers in the peritransplant period has improved outcomes of total pancreatectomy with islet autotransplantation (TPIAT). However, these drugs may suppress the immune system, resulting in severe infection.

METHODS

We retrospectively investigated the impact of microbial-contaminated islet product on posttransplant complications and metabolic outcomes of TPIAT patients receiving the IL-1β and TNF-blockade treatment at our center.

RESULTS

Among 108 TPIAT patients, 37 patients (34%) received contaminated products. Preoperative stent treatment and fibrosis score were independent risk factors for the contamination. There were no significant differences between the contaminated and noncontaminated product groups in posttransplant infectious complication rate, length of hospitalization, or readmission rate. However, islet equivalents (P < .0001) and insulin independence rate (P = .036) at 6 months were significantly lower for patients receiving contaminated product.

CONCLUSIONS

These results suggest that combined anti-inflammatory drug use is safe and well tolerated in TPIAT patients who receive contaminated islet product and does not increase the rate of infectious complications; however, contaminated islet product is associated with poor metabolic outcomes.

Geographical variance in reporting of elective surgery for chronic pancreatitis

The selection of optimum surgical procedure from the range of reported operations for chronic pancreatitis (CP) can be difficult. The aim of this study is to explore geographical variation in reporting of elective surgery for CP. A systematic search of the literature was performed using the Scopus database for reports of five selected procedures for CP: duodenum-preserving pancreatic head resection, total pancreatectomy with islet autotransplantation (TPIAT), Frey pancreaticojejunostomy, thoracoscopic splanchnotomy and the Izbicki V-shaped resection. The keyword and MESH heading 'chronic pancreatitis' was used. Overall, 144 papers met inclusion criteria and were utilized for data extraction. There were 33 reports of duodenum-preserving pancreatic head resection. Twenty-one (64%) were from Germany. There were 60 reports of TPIAT, 53 (88%) from the USA. There are only two reports of TPIAT from outwith the USA and UK. The 34 reports of the Frey pancreaticojejunostomy originate from 12 countries. There were 20 reports of thoracoscopic splanchnotomy originating from nine countries. All three reports of the Izbicki 'V' procedure are from Germany. There is geographical variation in reporting of surgery for CP. There is a need for greater standardization in the selection and reporting of surgery for patients with painful CP.

Diabetes-free survival after extended distal pancreatectomy and islet auto transplantation for benign or borderline/malignant lesions of the pancreas

Islet autotransplant is particularly attractive to prevent diabetes after extended pancreatectomy for benign or borderline/malignant pancreas disease. Between 2008 and 2018, 25 patients underwent left extended pancreatectomy (>60%) and islet autotransplant for a neoplasm located in the pancreatic neck or proximal body. Overall, disease-free and diabetes-free survivals were estimated and compared with those observed in 68 nondiabetic patients who underwent distal pancreatectomy for pancreatic neoplasms without islet autotransplant. Median follow-up was 4 years. We observed no deaths and a low morbidity (nonserious procedure-related complications in 2 of 25 patients). Patient and insulin-independent survival rates at 4 years were 100% and 96%, respectively. Glucose homeostasis remained within a nondiabetic range at all times for 19 (73%) of 25 patients. Preoperative glycemic level and insulin resistance were major predictors of diabetes development in these patients. Patients undergoing islet autotransplant had a longer diabetes-free survival than did patients without islet autotransplant (P = .04). In conclusion, islet autotransplant after extended pancreatic resection for neoplasms is a safe and successful procedure for preventing diabetes.

Glycemic Outcomes of Islet Autotransplantation

PURPOSE OF REVIEW

While there has been a growing utilization of total pancreatectomy with islet autotransplantation (TPIAT) for patients with medically refractory chronic pancreatitis over the past few decades, there remains a lack of consensus clinical guidelines to inform the counseling and management of patients undergoing TPIAT. In this article, we review the current clinical practice and published experience of several TPIAT centers, outline key aspects in managing patients undergoing TPIAT, and discuss the glycemic outcomes of this procedure.

RECENT FINDINGS

Aiming for lower inpatient glucose targets immediately after surgery (usually 100-120 mg/dl), maintaining all patients on subcutaneous insulin for at least 3 months to "rest" islets before an attempt is made to wean insulin, and close outpatient endocrinology follow-up after TPIAT particularly in the first year is common and related to better outcomes. Although TPIAT procedures and glycemic outcomes may differ across surgical centers, overall, approximately one third of patients are insulin independent at 1 year after TPIAT. Higher islet yield and lower preoperative glucose levels are among the strongest predictors of short-term post-operative insulin independence. Beyond 1 year post-operatively, the clinical management and long-term glycemic outcomes of patients after TPIAT are more variable. A multidisciplinary approach is essential in optimizing the preoperative, inpatient, and post-operative management and counseling of patients about the expected glycemic outcomes after surgery. Consensus guidelines for the clinical management of diabetes after TPIAT and harmonization of data collection protocols among TPIAT centers are needed to address the current knowledge gaps in clinical care and research and to optimize glycemic outcomes after TPIAT.

Liver transaminase levels after intraportal autologous islet transplantation after partial pancreatectomy were associated with long-term metabolic outcomes

AIMS

To investigate the changes of post-procedural liver transaminase levels after autologous islet transplantation (ITx), and their associations with glycemic outcomes.

METHODS

Non-diabetic patients who underwent distal pancreatectomy for benign tumors were enrolled. Islets isolated from the healthy part of the resected pancreas were transplanted via the portal vein. Metabolic parameters were evaluated in the subjects for 5 years.

RESULTS

Eight patients completed the study and four developed postoperative diabetes mellitus (PODM). Disposition index (DI) at postoperative 1 year showed prominent difference between the patients who develop PODM or not: DI was preserved in the PODM-free patients (49.7 ± 4.5 to 70.8 ± 14.4, P = 0.182), while it significantly decreased in the PODM patients (69.3 ± 9.9 to 28.5 ± 3.9, P = 0.019). The preoperative liver transaminase levels were not different between the two groups. However, transient increase in liver transaminase levels during the first week after ITx was observed only in the PODM patients, and their peak values demonstrated significant negative correlation with the changes in DI (r = -0.774 for alanine transaminase, r = -0.759 for aspartate transaminase; P < 0.05).

CONCLUSIONS

Elevation of serum transaminases after ITx could be one of the factors determining insulin secretion and PODM.

Incidental Neuroendocrine Tumor Discovered After Total Pancreatectomy Intended for Islet Autotransplantation: Important Considerations for Surgical Decision-Making

Total pancreatectomy (TP) is a treatment option for patients experiencing chronic pancreatitis (CP) refractory to medical management. Patients who are candidates for TP benefit from islet autotransplantation (IAT), which preserves available β-cell mass and thereby reduces the risk of brittle diabetes. Malignancy is an absolute contraindication for IAT to prevent the transplantation of occult malignant cells. We present the case of a patient with CP who was approved to undergo TP with IAT (TPIAT) but was intraoperatively discovered to have a pancreatic neuroendocrine tumor. The case illustrates a number of important surgical decision-making considerations for patients undergoing TPIAT and should help guide surgeons should they be presented with this clinical scenario. We stress the importance of vigilance for possible malignancy and to consider an intraoperative biopsy to further investigate unexpected findings that might represent an occult pancreatic malignancy in patients with CP undergoing TPIAT.

Duodenal graft complications requiring duodenectomy after pancreas and pancreas-kidney transplantation

Duodenal graft complications are poorly reported complications of pancreas transplantation that can result in graft loss. Excluding patients with early graft failure, after a median follow-up period of 126 months (range 23-198) duodenectomy was required in 14 of 312 pancreas transplants (4.5%). All patients were insulin-independent at the time of diagnosis. Reasons for duodenectomy included delayed duodenal graft perforation (n = 10, 71.5%) and refractory duodenal graft bleeding (n = 4, 28.5%). In patients with duodenal graft bleeding, a total duodenectomy was performed. In patients with duodenal graft perforation, preservation of a duodenal segment was possible in five patients but completion duodenectomy was necessary in one patient. After total duodenectomy, immediate enteric duct drainage was feasible in seven patients. In two patients, a pancreaticocutaneous fistula was created that was subsequently converted to enteric drainage in one patient. In the other patient, enteric fistulization occurred as a consequence of silent pressure perforation of the draining catheter on the ascending colon. After a mean follow-up period of 52 months (21-125), all patients were alive, well, and insulin-independent. An aggressive and timely surgical approach may permit graft rescue in patients with severe duodenal graft complications occurring after pancreas transplantation. Generalization of these results remains to be established.

Allo- and auto-percutaneous intra-portal pancreatic islet transplantation (PIPIT) for diabetes cure and prevention: the role of imaging and interventional radiology

Although the life expectancy of patients with type 1 diabetes mellitus (T1DM) has improved since the introduction of insulin therapy, the acute life-threatening and long-term complications from diabetes mellitus are significant causes of both mortality and morbidity. Percutaneous intra-portal pancreatic islet transplantation (PIPIT) is a minimally invasive, repeatable procedure which allows a β-cell replacement therapy through a liver islet engraftment, leading to insulin release and glycaemic control restoration in patients with diabetes. Allo-PIPIT, in which isolated and purified islets from cadaveric donor are used, does not require major surgery, and is potentially less expensive for the recipient. In case of long-term T1DM, islet-after-kidney (IAK) transplantation can simultaneously cure diabetes and chronic renal failure, while islet-transplant-alone (ITA) is performed in brittle, short-term T1DM, based on the infusion of an adequate islet mass and on a steroid-free immunosuppressive regimen according to the Edmonton protocol. Results of the Collaborative Islet Transplant Registry (CITR) demonstrate that allo-PIPIT reduces episodes of hypoglycemia and diabetic complications, and improves quality of life of diabetic patients. Auto-PIPIT, in which the own patient's islets are used, has been investigated as a preventive treatment for pancreatogenic diabetes in patients who undergo extensive pancreatectomy for malignant and non-malignant disease. This Review outlines the role of imaging and interventional radiology in allo- and auto-PIPIT.

Modeling the Iatrogenic Pancreatic Cancer Risk After Islet Autotransplantation in Mouse

Iatrogenic pancreatic cancer metastasis after islet infusion is a potential risk of islet autotransplantation performed after pancreatectomy. To model this risk, islets and/or pancreatic exocrine clusters obtained from a genetically engineered mouse model for pancreatic ductal adenocarcinoma (the LSL-Kras^G12D/+ ;LSL-Trp53^R172H/+ ;Pdx-1-Cre, termed KPC mouse) were transplanted via the portal vein in syngeneic wild type (WT) severely diabetic recipients in the following treatment groups: group A (n = 11) received KPC exocrine clusters in volume equal to 250 islet equivalents (IEQs); group B (n = 12) received 250 WT IEQs mixed with KPC exocrine clusters (1:1 volume ratio); group C (n = 5) received 250 KPC IEQs, and group D (n = 7) received 250 WT IEQs. The incidence of hepatic metastasis was assessed by magnetic resonance imaging and histology over the 13 months of follow-up. Overall survival was not different in the four groups. No mice developed liver metastases during the follow-up. Two mice developed spontaneous tumors: a liver hepatocellular tumor in group A and a malignant lymphoma in group D. Islets and/or exocrine clusters obtained by KPC mouse, a model that develops pancreatic cancer with 100% penetrance, do not retain the same risk of tumor development when transplanted via the portal vein in a syngeneic diabetic recipient.

Salvage Islet Auto Transplantation After Relaparatomy

BACKGROUND

To assess feasibility, safety, and metabolic outcome of islet auto transplantation (IAT) in patients undergoing completion pancreatectomy because of sepsis or bleeding after pancreatic surgery.

METHODS

From November 2008 to October 2016, approximately 22 patients were candidates to salvage IAT during emergency relaparotomy because of postpancreatectomy sepsis (n = 11) or bleeding (n = 11). Feasibility, efficacy, and safety of salvage IAT were compared with those documented in a cohort of 36 patients who were candidate to simultaneous IAT during nonemergency preemptive completion pancreatectomy through the pancreaticoduodenectomy.

RESULTS

The percentage of candidates that received the infusion of islets was significantly lower in salvage IAT than simultaneous IAT (59.1% vs 88.9%, P = 0.008), mainly because of a higher rate of inadequate islet preparations. Even if microbial contamination of islet preparation was significantly higher in candidates to salvage IAT than in those to simultaneous IAT (78.9% vs 20%, P < 0.001), there was no evidence of a higher rate of complications related to the procedure. Median follow-up was 5.45 ± 0.52 years. Four (36%) of 11 patients reached insulin independence, 6 patients (56%) had partial graft function, and 1 patient (9%) had primary graft nonfunction. At the last follow-up visit, median fasting C-peptide was 0.43 (0.19-0.93) ng/mL; median insulin requirement was 0.38 (0.04-0.5) U/kg per day, and median HbA1c was 6.6% (5.9%-8.1%). Overall mortality, in-hospital mortality, metabolic outcome, graft survival, and insulin-free survival after salvage IAT were not different from those documented after simultaneous IAT.

CONCLUSIONS

Our data demonstrate the feasibility, efficacy, and safety of salvage IAT after relaparotomy.

Single-centre experience of extending indications for percutaneous intraportal islet autotransplantation (PIPIAT) after pancreatic surgery to prevent diabetes: feasibility, radiological aspects, complications and clinical outcome

OBJECTIVE

Islet allotransplantation is a less invasive alternative to surgical pancreas transplantation for Type 1 diabetes, while percutaneous intraportal islet autotransplantation (PIPIAT) is usually performed after pancreatic surgery to prevent diabetes. Our aim was to assess the feasibility, radiological aspects, complications and clinical outcome of PIPIAT following pancreatic surgery for not only chronic pancreatitis but also benign and malignant nodules.

METHODS

From 2008 to 2012, 41 patients were enrolled for PIPIAT 12-48 h after pancreatic surgery (extended pancreatic surgery for chronic pancreatitis and benign/malignant neoplasms). PIPIAT was performed using a combined ultrasonography and fluoroscopy-guided technique (4-F catheter). PIPIAT feasibility, median follow-up and metabolic (insulin independence rate, graft function based on C-peptide levels) and oncologic outcomes were recorded.

RESULTS

PIPIAT was not performed in 7/41 patients (4 cases for an inadequate islet mass, 2 cases for haemodynamic instability and 1 case for islet culture contamination), while it was successfully performed in 34/34 patients. Procedure-related major complications occurred in four patients: two bleedings requiring transfusions, one patient with left portal vein thrombosis and one patient with sepsis. Median follow-up duration was 546 days. Insulin independence was achieved in 15/34 (44%) patients, partial graft function in 16/34 (47%) patients and no function in 3/34 (9%) patients. None of the 17 patients with malignant nodules developed liver metastases during follow-up.

CONCLUSION

PIPIAT, performed under ultrasound and fluoroscopy combined guidance and not requiring immunosuppression, is feasible, with a relatively low complication rate and a better metabolic outcome than allotransplantation.

ADVANCES IN KNOWLEDGE

PIPIAT can prevent pancreatogenic diabetes. Ultrasound is a useful tool for the guidance and monitoring of PIPIAT.

Autologous Islet Transplantation in Patients Requiring Pancreatectomy: A Broader Spectrum of Indications Beyond Chronic Pancreatitis

Islet autotransplantation (IAT) is usually performed in patients undergoing pancreatic surgery for chronic pancreatitis. In the present series, IAT was offered also to patients undergoing pancreatic surgery for both nonmalignant and malignant diseases, having either completion pancreatectomy as treatment for severe pancreatic fistulas (n = 21) or extensive distal pancreatectomy for neoplasms of the pancreatic neck (n = 19) or pancreatoduodenectomy because of the high risk of pancreatic fistula (n = 32). Fifty-eight of 72 patients who were eligible to this broader spectrum of indication actually received IAT. There was no evidence of a higher-than-expected rate of major complications for pancreatectomy. Forty-five patients receiving IAT were still alive at the time of the last scheduled follow-up (1375 ± 365 days). Eighteen (95%) of 19 and 11 (28%) of 39 patients reached insulin independence after partial or total pancreatectomy, respectively. The metabolic results were dependent on the transplanted islet mass. Thirty-one of 58 patients had malignant diseases of the pancreas or periampullary region, and only three patients developed ex novo liver metastases after IAT (median follow-up 914 ± 382 days). Our data demonstrate the feasibility, efficacy, and safety of IAT for a broader spectrum of clinical indications beyond chronic pancreatitis.

Microbial contamination of transplant solutions during pancreatic islet autotransplants is not associated with clinical infection in a pediatric population

BACKGROUND/OBJECTIVES

Total pancreatectomy and islet autotransplant (TP-IAT) is a potential treatment for children with severe refractory chronic pancreatitis. Cultures from the resected pancreas and final islet preparation are frequently positive for microbes. It is unknown whether positive cultures are associated with adverse outcomes in pediatric patients.

METHODS

We reviewed the medical records of children (n = 86) who underwent TP-IAT from May 2006-March 2015 with emphasis on demographics, previous pancreatic interventions, culture results, islet yield, hospital days, posttransplant islet function, and posttransplant infections. We compared outcomes in patients with positive (n = 57) and negative (n = 29) cultures.

RESULTS

Patients with positive cultures had higher rates of previous pancreas surgery (P = 0.007) and endoscopic retrograde cholangiopancreatography (P < 0.0001). Positive cultures were not associated with posttransplant infections (P = 1.00) or prolonged hospital length of stay (P = 0.29). Patients with positive final islet preparation culture showed increased rates of graft failure at 2 years posttransplant (P = 0.041), but not when adjusted for islet mass transplanted (P = 0.39).

CONCLUSIONS

Positive cultures during pediatric TP-IATs do not increase the risk of posttransplant infections or prolong hospital length of stay. Endocrine function depends on islet mass transplanted.

Pancreas Transplantation in the Modern Era

The field of pancreas transplantation has evolved from an experimental procedure in the 1980s to become a routine transplant in the modern era. With short- and long-term outcomes continuing to improve and the significant mortality, quality-of-life, and end-organ disease benefits, pancreas transplantation should be offered to more patients. In this article, we review current indications, patient selection, surgical considerations, complications, and outcomes in the modern era of pancreas transplantation.

Islet Volume and Indexes of β-Cell Function in Humans

Islet volume and endocrine pancreas architecture (islet size distribution) may be independent determinants of β-cell function. Furthermore, the accuracy of homeostatic model assessment (HOMA) indexes in predicting β-cell mass has never been assessed. Here we investigated the relationships between islet volume, islet density, and islet size distribution, estimated after pancreatic tissue digestion, with established indexes of β-cell function in humans. We included in this study 42 patients who were candidates for islet autotransplantation and had well-characterized glucose metabolism. Indexes of insulin secretion were calculated and compared with the islet volume, as a surrogate of β-cell mass, obtained after digestion of pancreas. Islet counting analysis showed considerable interindividual variation in islet density and size. Islet volume, but not density nor size, was the only independent determinant of β-cell function assessed by insulin HOMA β-cell. Islet volume was significantly reduced in the patients with overt hyperglycemia, but not in patients with impaired fasting glucose. Insulin HOMA β-cell predicted islet volume better than other measures of fasting insulin secretion. In conclusion, the present study documented a close direct relationship between indexes of β-cell function and islet volume in humans. The insulin HOMA β-cell provides a more reliable estimate of pancreatic islet volume than fasting glucose before islet isolation.

Diabetes after pancreatic surgery: novel issues

In the developed world, pancreatic surgery is becoming more common, with an increasing number of patients developing diabetes because of either partial or total pancreatectomy, with a significant impact on quality of life and survival. Although these patients are expected to consume increasing health care resources in the near future, many aspects of diabetes after pancreatectomy are still not well defined. The treatment of diabetes in these patients takes advantage of the therapies used in type 1 and 2 diabetes; however, no specific guidelines for its management, both immediately after pancreatic surgery or in the long term, have been developed. In this article, on the basis of both the literature and our clinical experience, we address the open issues and discuss the most appropriate therapeutic options for patients with diabetes after pancreatectomy.

Re-engineering islet cell transplantation

We are living exciting times in the field of beta cell replacement therapies for the treatment of diabetes. While steady progress has been recorded thus far in clinical islet transplantation, novel approaches are needed to make cell-based therapies more reproducible and leading to long-lasting success. The multiple facets of diabetes impose the need for a transdisciplinary approach to attain this goal, by targeting immunity, promoting engraftment and sustained functional potency. We discuss herein the emerging technologies applied to this rapidly evolving field.

Laparoscopic robot-assisted versus open total pancreatectomy: a case-matched study

BACKGROUND

The enhanced dexterity offered by robotic assistance could be excessive for distal pancreatectomy but not enough to improve the outcome of laparoscopic pancreaticoduodenectomy. Total pancreatectomy retains the challenges of uncinate process dissection and digestive reconstruction, but avoids the risk of pancreatic fistula, and could be a suitable operation to highlight the advantages of robotic assistance in pancreatic resections.

METHODS

Eleven laparoscopic robot-assisted total pancreatectomies (LRATP) were compared to 11 case-matched open total pancreatectomies. All operations were performed by one surgeon during the same period of time. Robotic assistance was employed in half of the patients, based on robot availability at the time of surgery. Variables examined included age, sex, American Society of Anesthesiologists score, body mass index, estimated blood loss, need for blood transfusions, operative time, tumor type, tumor size, number of examined lymph nodes, margin status, post-operative complications, 90-day or in-hospital mortality, length of hospital stay, and readmission rate.

RESULTS

No LRATP was converted to conventional laparoscopy, hand-assisted laparoscopy or open surgery despite two patients (18.1 %) required vein resection and reconstruction. LRATP was associated with longer mean operative time (600 vs. 469 min; p = 0.014) but decreased mean blood loss (220 vs. 705; p = 0.004) than open surgery. Post-operative complications occurred in similar percentages after LRATP and open surgery. Complications occurring in most patients (5/7) after LRATP were of mild severity (Clavien-Dindo grade I and II). One patient required repeat laparoscopic surgery after LRATP, to drain a fluid collection not amenable to percutaneous catheter drainage. One further patient from the open group required repeat surgery because of bleeding. No patient had margin positive resection, and the mean number of examined lymph nodes was 45 after LRATP and 36 after open surgery.

CONCLUSIONS

LRATP is feasible in selected patients, but further experience is needed to draw final conclusions.

Autologous islet transplantation in patients requiring pancreatectomy for neoplasm

Autologous islet cell transplantation is a procedure performed to prevent or reduce the severity of diabetes after pancreatic resection. Autologous islet cell transplantation is being used almost exclusively in patients undergoing pancreatectomy because of painful, chronic pancreatitis, or multiple recurrent episodes of pancreatitis that is not controlled by standard medical and surgical treatments. Here, we discuss the possibility of extending the clinical indications for this treatment on the basis of our experience in patients undergoing pancreatic surgery for both nonmalignant and malignant diseases, including patients undergoing completion pancreatectomy because of anastomosis leakage after pancreaticoduodenectomy and those with pancreatic anastomosis deemed at high risk for failure.

Total pancreatectomy with islet cell auto-transplantation: update and outcomes from major centers

OPINION STATEMENT

Chronic pancreatitis is the result of irreversible damage to pancreatic acinar cells, and can result in debilitating chronic pain for patients. Treatment centers on pain relief, often with chronic narcotic use. Surgical therapy consists of both resection procedures to remove affected pancreatic parenchyma and drainage procedures to facilitate drainage of the main pancreatic duct. Total pancreatectomy historically was utilized in extreme cases due to the brittle glucose control that followed from the total loss of islet cells. Total pancreatectomy with islet cell auto-transplantation (TP-AIT) is gaining in popularity due to the maintenance of beta cell mass and the ability of patients to potentially be insulin independent post-operatively. TP-AIT is very helpful in the treatment of pain for patients with chronic pancreatitis. The overall majority of patients have an improvement in pain and quality-of-life scores. AIT also allows the majority of patients to have minimal insulin requirements post-operatively. With proper patient selection, these outcomes can be achieved.