The efficacy of on-site evaluation for identification of transplant pancreas.

Objective: Pancreatic transplantation has been relatively uncommon until the last 2 decades, but is now an accepted therapeutic intervention for type I diabetes. Core biopsies of pancreas transplants are frequently performed to rule out rejection, which is a leading cause of graft failure. Often, it is difficult to localize the graft for biopsy by imaging. Our objective was to determine whether on-site assessment by cytopathology can assist in procedure protocols for biopsy of pancreas transplants. Study Design: We reviewed cytology and surgical pathology reports from 68 instances of pancreas transplant biopsy at our institution and evaluated the correlation between cytology (fine needle aspiration, touch preparation or both) and the final core biopsy. Results: Pancreatic tissue was identified by on-site assessment in 56/68 cases and was present on core biopsy in 53/68 cases. There were 3 cases where fine needle aspiration/touch preparation results were not concordant with final core biopsy results. The positive predictive value of a positive on-site assessment was 96.4%. More importantly, the negative predictive value of on-site assessment was 100%. Conclusions: On-site evaluation by cytopathology is highly effective for the identification of transplant pancreas. In cases where no pancreatic tissue is identified by on-site assessment, relocalization of the biopsy needle is recommended.