Pancreas Transplantation for Type 2 Diabetes: A Systematic Review, Critical Gaps in the Literature, and a Path Forward

Four Decades of Research Productivity and Hot Spots in Pancreas Transplantation

Background: The field of pancreas transplantation has undergone transformative phases, progressing from its promising inception in 1966 to becoming a standard treatment for patients with insulin-dependent diabetes. This bibliometric analysis explores the progression of pancreas transplantation research over a period of four decades, mapping milestones, contributors, and emerging trends. Methods: Our bibliometric analysis utilizes the comprehensive Scopus database, which includes publication titles, author information, affiliations, abstracts, keywords, and journal details. The search strategy was centered on research related to pancreas and pancreas-kidney transplantation. The analysis encompasses the time frame spanning from 1983 to 2023, with the data extraction taking place on October 7th, 2023. Results: The analysis of 4,897 articles uncovered unique trends in the field of pancreas transplantation research. The years 1989, 1996, and 2021 saw significant increases in the number of publications, which corresponded to the responses to clinical challenges and advancements. Contributions by authors from the United States of America were the most numerous, with 1,905 publications and 49,949 citations. The research topics were highlighted by keywords such as "graft survival," "graft rejection," and" Immunosuppressive treatment." Conclusion: The fluctuations in publication trends that have been identified indicate dynamic reactions to changing priorities and challenges. Although it has limitations, this analysis provides valuable insights for researchers, clinicians, and policymakers who are dealing with the complex field of pancreas transplantation literature. Further bibliometric research may advance our knowledge and direct future initiatives in this developing field.

Stem Cell-Derived Islet Transplantation in Patients With Type 2 Diabetes: Can Diabetes Subtypes Guide Implementation?

Historically, only patients with brittle diabetes or severe recurrent hypoglycemia have been considered for islet transplantation (ITx). This population has been selected to optimize the risk-benefit profile, considering risks of long-term immunosuppression and limited organ supply. However, with the advent of stem cell (SC)-derived ITx and the potential for immunosuppression-free ITx, consideration of a broader recipient cohort may soon be justified. Simultaneously, the classical categorization of diabetes is being challenged by growing evidence in support of a clustering of disease subtypes that can be better categorized by the All New Diabetics in Scania (ANDIS) classification system. Using the ANDIS classification, 5 subtypes of diabetes have been described, each with unique causes and consequences. We evaluate consideration for ITx in the context of this broader patient population and the new classification of diabetes subtypes. In this review, we evaluate considerations for ITx based on novel diabetes subtypes, including their limitations, and we elaborate on unique transplant features that should now be considered to enable ITx in these "unconventional" patient cohorts. Based on evidence from those receiving whole pancreas transplant and our more than 20-year experience with ITx, we offer recommendations and potential research avenues to justify implementation of SC-derived ITx in broader populations of patients with all types of diabetes.

When pancreata fly: Outcomes and lessons learned from the development of a Pancreas Transplant Import Program

BACKGROUND

To address long waitlist times and increase pancreas transplantation, our center has implemented a protocol for long-distance importation of pancreata.

METHODS

We conducted a retrospective review of pancreas transplantation at our institution from January 1, 2014, the start of our importation program, through September 30, 2021. Outcomes were compared between locally procured grafts and imported grafts, defined as grafts procured greater than 250 nautical miles (NM) from our center.

RESULTS

Eighty-one patients underwent pancreas transplantation during the study time period; 19 (23.5%) received imported grafts. There were no significant differences in recipient demographics or type of transplant received. Mean distance of import was 644.2 ± 234.0 NM. Imported grafts were more likely to be from pediatric donors <18 years old (p = .02) and a significantly higher proportion of imported grafts came from donors weighing <30 kg (26.3 vs. 3.2%, p = .007). Cold ischemic time was longer for imported grafts than for local grafts (13.4 ± 2.3 h vs. 9.8 ± 2.2 h, p < .01). There was no significant difference in deaths or graft losses within 90 days or at 1 year between groups.

CONCLUSION

Centers should consider expanding criteria for acceptance of imported pancreata to increase the number of transplants and combat organ nonutilization.

Modern indications for referral for kidney and pancreas transplantation

PURPOSE OF REVIEW

Pancreas transplantation (PTx) is currently the only therapy that can predictably achieve sustained euglycemia independent of exogenous insulin administration in patients with insulin-dependent diabetes mellitus. This procedure involves a complex abdominal operation and lifetime dependence on immunosuppressive medications. Therefore, PTx is most frequently performed in combination with other organs, usually a kidney transplant for end stage diabetic nephropathy. Less frequently, solitary PTx may be indicated in patients with potentially life-threatening complications of diabetes mellitus. There remains confusion and misperceptions regarding indications and timing of patient referral for PTx.

RECENT FINDINGS

In this review, the referral, evaluation, and listing process for PTx is described, including a detailed discussion of candidate assessment, indications, contraindications, and outcomes.

SUMMARY

Because the progression of diabetic kidney disease may be less predictable than other forms of kidney failure, early referral for planning of renal and/or pancreas transplantation is paramount to optimize patient care and allow for possible preemptive transplantation.