Correlation of Pancreatic Fibrosis and Post Islet Cell Autotransplantation (IAT) Liver Biopsy with Islet Cell Yield and Insulin Requirement in Patients Undergoing Total Pancreatectomy (TP) with IAT
Charmi Patel, Judith L Pugh, Marina Vardanyan, Brianna Brigsby, Chirag Desai, Tun Jie, Khalid Khan, Angelika C Gruessner, Reiner WG Gruessner, Achyut K Bhattacharyya, Horacio Rilo. University of Arizona, Tucson, AZ
Background: In patients with chronic pancreatitis (CP), TP with IAT can preserve endocrine function and help manage the complications of diabetes. The factors that determine the success of TP-IAT have not been clearly defined. The aim of our study is 2 fold: 1) to correlate the histopathological finding of pancreatic fibrosis with islet yield and function, and 2) to determine the usefulness of post IAT liver biopsy in assessment of islet engraftment.
Design: From 2009-2011, a total of 25 patients underwent TP with IAT. Islet yield is calculated in islet equivalents per kg (IEQ/kg) for each patient. 21(84%) patients underwent pancreatic biopsy. The histologic degree and extent of fibrosis is scored by a pathologist from a score of 1 to 6 (Detlefsen et al, Virchows Arch 2005). The correlation between fibrosis and islet yield is evaluated (Kendall Tau b correlation). 22(88%) patients underwent transplant liver biopsy. The pre and post IAT liver biopsies are evaluated with H & E sections as well as with immunohistochemical (IHC) stains (Synaptophysin, CD56, Insulin and Glucagon) to determine islet engraftment. Insulin requirement at the time of discharge for patients with TP-IAT (n=21) is compared to that of patients with TP without IAT (n=12).
Results: Islet recovery correlates negatively with pancreatic fibrosis (r = -0.506). Mean islet recovery is 4426 IEQ/kg (range 76-19744) with a mean fibrosis score of 4.22. Out of 21 patients, only 2 patients show positive IHC staining for Insulin and Glucagon in post-transplant liver biopsies irrespective of IEQ/kg yield. The patients with TP-IAT had a significant lower insulin requirement at the time of discharge than patients who underwent TP alone (P < 0.001). The median insulin requirement for the group with TP-IAT is 11 units (range 4-32), while median for the group with TP only is 26.5 units (range 5-120).
Conclusions: The histologic change of fibrosis in the pancreas at the time of TP clearly correlates with islet yield. Our data suggest that TP- IAT should be considered in the early phase of CP to better preserve beta cell mass. Our study clearly demonstrates that post operative liver biopsy is not a useful tool for the evaluation of successful engraftment. TP-IAT is an effective and safe procedure to prevent or minimize postsurgical diabetes for patients with CP requiring TP.
Tuesday, March 20, 2012 9:30 AM
Poster Session III # 257, Tuesday Morning