Assessment of simple indices based on a single fasting blood sample as a tool to estimate beta-cell function after total pancreatectomy with islet autotransplantation - a prospective 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.

Pretransplant HOMA-β Is Predictive of Insulin Independence in 7 Patients With Chronic Pancreatitis Undergoing Islet Autotransplantation

Islet and β-cell function is intrinsic to glucose homeostasis. Pancreatectomy and islet autotransplantation (PIAT) for chronic pancreatitis (CP) treatment is a useful model for assessing islet function in the absence of immune-suppression and to perform extensive presurgical metabolic evaluations not possible from deceased donors. We recently showed that in CP-PIAT patients, preoperative islet identity loss presented with postoperative glycemic loss. Here, we examine presurgical islet function using Homeostatic Model Assessment-Beta Cell Function (%) (HOMA-β) and glycemic variables and compared them with postsurgical insulin independence and their predicted alignment with Secretory Unit of Islet Transplant Objects (SUITO) and beta cell score after transplantation (BETA-2) scores.

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.

Predictors of Glycemic Outcomes at 1 Year Following Pediatric Total Pancreatectomy With Islet Autotransplantation

OBJECTIVE

Total pancreatectomy with islet autotransplantation (TPIAT) is indicated to alleviate debilitating pancreas-related pain and mitigate diabetes in patients with acute recurrent and chronic pancreatitis when medical/endoscopic therapies fail. Our aim was to evaluate predictors of insulin requirement at 1 year following TPIAT in a cohort of children.

RESEARCH DESIGN AND METHODS

This was a review of 43 pediatric patients followed after TPIAT for 1 year or longer. Primary outcome was insulin use at 1 year, categorized as follows: insulin independent, low insulin requirement (<0.5 units/kg/day), or high insulin requirement (≥0.5 units/kg/day).

RESULTS

At 1 year after TPIAT, 12 of 41 (29%) patients were insulin independent and 21 of 41 (51%) had low and 8 of 41 (20%) had high insulin requirement. Insulin-independent patients were younger than those with low and high insulin requirement (median age 8.2 vs. 14.6 vs. 13.1 years, respectively; P = 0.03). Patients with insulin independence had a higher number of transplanted islet equivalents (IEQ) per kilogram body weight (P = 0.03) and smaller body surface area (P = 0.02), compared with those with insulin dependence. Preoperative exocrine insufficiency was associated with high insulin requirement (P = 0.03). Higher peak C-peptide measured by stimulated mixed-meal tolerance testing (MMTT) at 3 and 6 months post-TPIAT was predictive of lower insulin requirement at 1 year (P = 0.006 and 0.03, respectively).

CONCLUSIONS

We conclude that insulin independence following pediatric TPIAT is multifactorial and associated with younger age, higher IEQ per kilogram body weight transplanted, and smaller body surface area at time of operation. Higher peak C-peptide measured by MMTT following TPIAT confers a higher likelihood of low insulin requirement.

Pain resolution and glucose control in pediatric patients with chronic pancreatitis after total pancreatectomy with islet auto-transplantation

BACKGROUND

Chronic pancreatitis (CP) and acute recurrent pancreatitis (ARP) in pediatric patients are strongly associated with genetic mutations and lead to pan-parenchymal disease refractory to medical and endoscopic treatment. Our aim was to assess pain resolution and glucose control in patients with CP and ARP following total pancreatectomy with islet auto-transplantation (TPIAT).

METHODS

We retrospectively analyzed prospectively collected clinical data of 12 children who developed CP and ARP and underwent TPIAT when 21 years old or younger at the University of Chicago between December 2009 and June 2020. Patients with recurrent or persistent abdominal pain attributed to acute or chronic pancreatic inflammation and a history of medical interventions attempted for the relief of pancreatic pain were selected by a multi-disciplinary team for TPIAT. We followed patients post-operatively and reported data for pre-TPIAT, post-operative day 75, and yearly post-TPIAT.

RESULTS

All 12 patients experienced complete resolution of pancreatic pain. The overall insulin-independence rate after 1 year was 66% (8/12) and 50% (3/6) at 4 years. Shorter duration of CP/ARP pre-TPIAT, higher mass of islets infused, and lower BMI, BMI percentile, and BSA were associated with insulin-independence post-TPIAT.

CONCLUSIONS

TPIAT is a viable treatment option for pediatric patients with CP and ARP. Pediatric patients undergoing TPIAT for CP achieved resolution of pancreatic-type pain and reduced opioid requirements. The majority were able to achieve insulin-independence which was associated with lower pre-TPIAT BMI and higher islet mass transplanted (i.e., over 2000 IEQ/kg), the latter of which can be achieved by earlier TPIAT.

LEVEL OF EVIDENCE

Treatment study, Level IV.

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.

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.

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

The Igls criteria assess islet function after islet allotransplant, based on C-peptide, insulin use, hemoglobin A1c, and severe hypoglycemia. However, these criteria as currently defined cannot be applied to total pancreatectomy islet autotransplant (TPIAT) patients. We tested modified criteria for assessing islet function in a large cohort of TPIAT patients (n = 379). Metabolic outcomes were assessed. We assigned Auto-Igls class to each patient as able and evaluated the utility, validity, and perioperative risk factors of Auto-Igls at 1-year post-IAT. We tested the association of Auto-Igls with independent measures of islet graft function, specifically continuous glucose monitoring (CGM) data or acute C-peptide response to glucose (ACRglu) from intravenous glucose tolerance tests. An Auto-Igls class was assigned to 264 patients (69%). Among patients who could not be classified, most were missing exact insulin dose. Seventy-three percent of TPIAT recipients were classified as optimal or good at 1 year. The only significant predictor of Auto-Igls class was islet mass transplanted (P < 0.0001). Auto-Igls class was associated with percent time in range (70-140 mg/dl) on CGM (P = 0.02) and ACRglu (P < 0.0001). Modified Igls classification for IAT permits simple, comprehensive assessment of metabolic outcomes after TPIAT and is associated with other islet functional measures.

Immediate Postoperative Insulin Requirements May Predict Metabolic Outcome after Total Pancreatectomy and Islet Autotransplantation

Chronic pancreatitis (CP) is a progressive disease that leads to eventual loss of endocrine and exocrine function. Total pancreatectomy and islet autotransplantation (TPIAT) is a treatment option for patients with CP; however, predicting postoperative metabolic outcomes remains elusive. In this single-center retrospective study, we report pre-TPIAT characteristics, beta cell function indices, islet yield, and post-TPIAT glucose management data to further understand their relationship. Islet yield, glucose level, and insulin requirement for 72 hours postoperatively were collected for a total of 13 TPIAT recipients between 9-2013 and 9-2018. In addition, their glucose control and basal insulin requirements at 3, 6, and 12 months post-TPIAT were analyzed. All 13 subjects had normal baseline fasting glucose levels. Median islet yield was 4882 IEq/kg (interquartile range 3412 to 8987). Median postoperative total insulin requirement on day 3 was 0.43 units/kg. Pre-TPIAT baseline glucose, insulin, or c-peptide level did not have a significant correlation with the islet yield. Similarly, there was no correlation between islet yield and insulin requirement at 72-hour postoperatively. However, there was an inverse correlation between the absolute islet yield (IEq) and insulin requirement at 6 months and 12 months following post-TPIAT. Further analysis of the relationship between 72-hour post-op insulin requirement and insulin requirement at discharge, 3, 6, and 12 months showed a positive correlation. Despite the finding of inverse correlation of islet yield with long-term basal insulin requirement, this study was not able to detect a correlation between the preoperative parameters to postoperative short-term or long-term outcome as noted in other studies. The 72-hour postoperative insulin requirement is a helpful postoperative predictor of patients needing long-term insulin management following TPIAT. This observation may identify a high-risk group of patients in need of more intensive diabetes education and insulin treatment prior to hospital discharge.

Utility of arginine stimulation testing in preoperative assessment of children undergoing total pancreatectomy with islet autotransplantation

Metabolic outcomes after total pancreatectomy with islet autotransplantation (TPIAT) are influenced by the islet mass transplanted. Preclinical and clinical studies indicate that insulin and C-peptide levels measured after intravenous administration of the beta cell secretagogue arginine can be used to estimate the available islet mass. We sought to determine if preoperative arginine stimulation test (AST) results predicted transplanted islet mass and metabolic outcomes in pediatric patients undergoing TPIAT. We evaluated the association of preoperative C-peptide and insulin responses to AST with islet isolation metrics using linear regression, and with postoperative insulin independence using logistic regression. Twenty-six TPIAT patients underwent preoperative AST from 2015 to 2018. The acute C-peptide response to arginine (ACRarg) was correlated with isolated islet equivalents (IEQ; r = 0.59, P = 0.002) and islet number (IPN; r = 0.48, P = 0.013). The acute insulin response to arginine (AIRarg) was not significantly correlated with IEQ (r = 0.38, P = 0.095) or IPN (r = 0.41, P = 0.071). Neither ACRarg nor AIRarg was associated with insulin use at 6 months postoperatively. Preoperative C-peptide response to arginine correlates with islet mass available for transplant in pediatric TPIAT patients. AST represents an additional tool before autotransplant to provide counseling on likely islet mass and to inform quality improvements of islet isolation techniques.