Real-Time Histologic Assessment of CT-Guided Percutaneous Needle Core Biopsies of the Transplant Pancreas
Rebecca Wilcox, Anant D Bhave, Pamela Gibson. Fletcher Allen Health Care (FAHC)/University of Vermont (UVM), Burlington; FAHC/UVM, Burlington
Background: Gold standard for detecting pancreatic transplant rejection is percutaneous needle biopsy, guided by US or CT. Biopsy adequacy is defined as pancreatic samples containing at least 2 acinar tissue lobules associated with 2-3 septal areas. Although this is an effective method it is not absolute (reported yield for adequate tissue 83-90%). Objective: To test whether real-time (RT) histologic assessment of CT-guided biopsies of allograft pancreases could improve the success rate of obtaining tissue adequate for histopathologic analysis.
Design: From 1/2009 - 10/2011 all pancreatic allograft biopsies followed the RT assessment protocol. The intervention radiologist contacted the transplant pathologist at time of biopsy. Within the IR suite the biopsy, on saline soaked telfa within a Petri dish, was assessed by standard light microscopy (stage lowered). At 4X the fresh tissue was examined for lobular acinar tissue (defined adequate). The radiologist, generally present at the microscope, was directly informed of inadequate tissue so additional passes/biopsies could be obtained. Adequate biopsies were placed into 10% buffered formalin and subsequently processed by standard techniques. Yield results were compared to 5-yr (2004-2008) data prior to study procedure.
Results: Results demonstrated that it is possible to identify pancreatic acinar lobules in fresh tissue under a standard microscope (Figure 1) with distinction from non-acinar tissue (e.g. adipose tissue, fibrosis). Adequate tissue for subsequent evaluation (H&E slides) for transplant rejection was obtained in 8/8 cases during the study period (100% yield), compared to 14/18 cases (78% yield) in 5 yrs prior.
Conclusions: Obtaining pancreatic biopsies adequate for R/O transplant rejection can be difficult, especially in cases with abundant capsular reaction. Histologic assessment of fresh tissue biopsies on site can increase the rate of success, particularly in institutions that infrequently perform these biopsies. Most academic centers have a microscope available in their IR suite for evaluations of FNA specimens; therefore, this increase in yield can occur without additional cost or new equipment.
Monday, March 19, 2012 1:00 PM
Poster Session II # 304, Monday Afternoon