Performance of modified Igls criteria to evaluate islet autograft function after total pancreatectomy with islet autotransplantation - a retrospective study

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.

Nutrition challenges following total pancreatectomy with islet autotransplantation

Total pancreatectomy with islet autotransplantation (TPIAT) is a surgical treatment option for patients with chronic pancreatitis who have not responded to other therapies. TP offers pain relief whereas IAT preserves beta cell mass to reduce endocrine insufficiency. During the surgical procedure, the entire pancreas is removed. Islet cells from the pancreas are then isolated, purified, and infused into the liver via the portal vein. Successful TPIAT relieves pain for a majority of patients but is not without obstacles, specifically gastrointestinal, exocrine, and endocrine challenges. The postoperative phase can be complicated by gastrointestinal symptoms causing patients to have difficulty regaining adequate oral intake. Enteral nutrition is frequently provided as a bridge to oral diet. Patients undergoing TPIAT must be monitored for macronutrient and micronutrient deficiencies following the procedure. Exocrine insufficiency must be treated lifelong with pancreatic enzyme replacement therapy. Endocrine function must be monitored and exogenous insulin provided in the postoperative phase; however, a majority of patients undergoing TPIAT require little or no long-term insulin. Although TPIAT can be a successful option for patients with chronic pancreatitis, nutrition-related concerns must be addressed for optimal recovery.

Assessment of long-term graft function following total pancreatectomy and autologous islet transplantation: the Leicester experience

Background

Total pancreatectomy and islet autotransplantation (TPIAT) is a recognised treatment for chronic pancreatitis (CP) with the potential to mitigate or prevent pancreatogenic diabetes. We present our 10-year follow-up of TPIAT patients.

Methods

The University Hospitals of Leicester performed 60 TPIAT procedures from September 1994 to May 2011. Seventeen patients completed their 10-year assessment and were grouped using the modified Auto-Igls criteria; good response, n=5 (insulin-independent for first 5 years post-TPIAT); partial response, n=6 (insulin requirements <20 iU/day post-TPIAT) and poor response, n=6 (insulin requirements ≥20 iU/day post-TPIAT). C-peptide, haemoglobin A1c (HbA1c) and oral glucose tolerance test (OGTT) were undertaken preoperatively (baseline), then at 3, 6 months and then yearly for 10 years. Data was analysed using analysis of variance (ANOVA).

Results

Median C-peptide levels were significantly higher, 120 minutes following OGTT, in the "good response" compared to "partial" and "poor" groups (two-way ANOVA test, P<0.0001). All groups demonstrated preservation of C-peptide release. HbA1c levels were significantly lower in the "good response" compared to "partial" and "poor" groups (two-way ANOVA test, P<0.0003 and P<0.0001). Median fasting glucose levels at 30 and 120 min following OGTT, were significantly lower in the "good response" compared to "partial" and "poor" groups (two-way ANOVA test, P<0.0001 and P<0.0001).

Conclusions

TPIAT preserves long-term islet graft functions in 10-year follow up. Even in patients in the poor response group, there is evidence of C-peptide release (>0.5 ng/mL) after OGTT stimulation potentially preventing long-term diabetes-related complications.

Effectiveness of Intraoperative Versus Dedicated Islet Cell Laboratory Isolation for Total Pancreatectomy With Islet Autotransplant

Background.

Total pancreatectomy with islet autotransplantation (TPIAT) requires a complex islet isolation process of the explanted pancreas. Islet isolation has historically required a specialized laboratory to perform islet isolation. We report our experience with a novel technique of intraoperative islet isolation that does not require a specialized islet laboratory, thereby making the isolation process simpler, more accessible, and less costly.

Methods.

We performed a retrospective, comparative effectiveness analysis of 50 adult patients who underwent TPIAT from 2012 to 2020 (TPIAT with remote isolation [n = 20] versus intraoperative isolation of islet cells [n = 30]). The primary outcome was islet equivalents per body weight (IEQ/kg) for patients in each group.

Results.

Mean IEQ/kg‘s (4294 remote group versus 3015 intraoperative group, P = 0.06) and 1-y postoperative C-peptide levels (1.51 ng/mL remote group versus 0.91 ng/mL intraoperative group, P = 0.10) were not different between groups. Mean 1-y HbA1c levels (7.7% in the remote group versus 7.1% intraoperative group, P = 0.67) and 1-y insulin requirements (P = 0.31) were not statistically different. Lower average cost of hospitalization was seen in the intraoperative group, although this was not statistically significant ($104 398 remote versus $78 986 intraoperative, P = 0.81).

Conclusions.

Intraoperative islet isolation has similar effectiveness in regard to glycemic outcomes compared with the use of a dedicated islet cell isolation laboratory at a lower cost.

Quality of life and metabolic outcomes after total pancreatectomy and simultaneous islet autotransplantation

Background

Pancreas surgery remains technically challenging and is associated with considerable morbidity and mortality. Identification of predictive risk factors for complications have led to a stratified surgical approach and postoperative management. The option of simultaneous islet autotransplantation (sIAT) allows for significant attenuation of long-term metabolic and overall complications and improvement of quality of life (QoL). The potential of sIAT to stratify a priori the indication for total pancreatectomy is yet not adequately evaluated.

Methods

The aim of this analysis was to evaluate the potential of sIAT in patients undergoing total pancreatectomy to improve QoL, functional and overall outcome and therefore modify the surgical strategy towards earlier and extended indications. A center cohort of 24 patients undergoing pancreatectomy were simultaneously treated with IAT. Patients were retrospectively analyzed regarding in-hospital and overall mortality, postoperative complications, ICU stay, hospital stay, metabolic outcome, and QoL.

Results

Here we present that all patients undergoing primary total pancreatectomy or surviving complicated two-stage pancreas resection and receiving sIAT show excellent metabolic outcome (33% insulin independence, 66% partial graft function; HbA1c 6,1 ± 1,0%) and significant benefit regarding QoL. Primary total pancreatectomy leads to significantly improved overall outcome and a significant reduction in ICU- and hospital stay compared to a two-stage completion pancreatectomy approach.

Conclusions

The findings emphasize the importance of risk-stratified pancreas surgery. Feasibility of sIAT should govern the indication for primary total pancreatectomy particularly in high-risk patients. In rescue completion pancreatectomy sIAT should be performed whenever possible due to tremendous metabolic benefit and associated QoL.

Pancreas surgery is complicated and associated with substantial risks and even danger of death. The surgical removal of the whole pancreas can be necessary for some indications but results in a severe form of diabetes. The method of islet autotransplantation (IAT) involves taking the pancreas, isolating the insulin-producing cells and returning these to the patient. This helps to preserve insulin production and minimises the impact of diabetes. We retrospectively analyzed a cohort of patients undergoing pancreatectomy that were simultaneously treated with IAT. The analysis included short-term and long-term surgical and diabetes-related outcomes as well as quality of life. All parameters indicated the benefit of IAT in patients that require extensive pancreas surgery. Offering IAT to patients may reduce surgical complications after pancreatectomy, enhance recovery, and therefore facilitate faster initiation of other therapies where needed.

Ludwig and Distler et al. evaluate quality of life and metabolic outcomes in patients undergoing total pancreatectomy and simultaneous islet autotransplantation. The authors report benefits in terms of glycemic control, as well as improvements in quality of life, following the procedure.

Examination of the Igls Criteria for Defining Functional Outcomes of β-cell Replacement Therapy: IPITA Symposium Report

CONTEXT

The Igls criteria were developed to provide a consensus definition for outcomes of β-cell replacement therapy in the treatment of diabetes during a January 2017 workshop sponsored by the International Pancreas & Islet Transplant Association (IPITA) and the European Pancreas & Islet Transplant Association. In July 2019, a symposium at the 17th IPITA World Congress was held to examine the Igls criteria after 2 years in clinical practice, including validation against continuous glucose monitoring (CGM)-derived glucose targets, and to propose future refinements that would allow for comparison of outcomes with artificial pancreas system approaches.

EVIDENCE ACQUISITION

Utilization of the criteria in various clinical and research settings was illustrated by population as well as individual outcome data of 4 islet and/or pancreas transplant centers. Validation against CGM metrics was conducted in 55 islet transplant recipients followed-up to 10 years from a fifth center.

EVIDENCE SYNTHESIS

The Igls criteria provided meaningful clinical assessment on an individual patient and treatment group level, allowing for comparison both within and between different β-cell replacement modalities. Important limitations include the need to account for changes in insulin requirements and C-peptide levels relative to baseline. In islet transplant recipients, CGM glucose time in range improved with each category of increasing β-cell graft function.

CONCLUSIONS

Future Igls 2.0 criteria should consider absolute rather than relative levels of insulin use and C-peptide as qualifiers with treatment success based on glucose assessment using CGM metrics on par with assessment of glycated hemoglobin and severe hypoglycemia events.