The impact of pathologist experience on liver transplant biopsy interpretation.

We studied the impact of pathologist experience on liver transplant biopsy interpretation for cases designated 'nonspecific' by pathologists at a nontransplant center. Among 102 consecutive liver transplant biopsies from 92 patients performed at the Foothills Medical Center, 30 liver biopsies from 23 patients were designated 'nonspecific' by the local pathologist. These biopsy slides were independently reviewed by an expert in liver transplant pathology at a major US transplant center. The expert pathologist was given only the information on the original requisition. In seven biopsies from five patients, there was full agreement between the external expert and the local pathologist. In 10 biopsies from six patients, the expert concurred with the initial assessment but emphasized critical negatives such as 'no evidence of rejection or recurrent hepatitis'. A discrepant diagnosis was found in 13 biopsies from 12 patients. In five biopsies from four patients, the revised diagnoses were inaccurate due to insufficient or misleading clinical information on the requisition. In eight biopsies from eight patients, the revised diagnoses were proven to be correct by clinicopathologic correlation. Our study shows that pathology expertise helped to clarify the diagnosis in about 27% of cases, which justifies the cost of obtaining a second opinion in difficult biopsies. Misinterpretation by the expert pathologist in up to 17% of biopsies highlights the importance of direct communication between hepatologist and pathologist in order to achieve a correct diagnosis. Familiarity with those cases with relatively uncommon histology, a diligent search for subtle morphologic changes, and use of standard terminology could improve the quality of liver transplant biopsy interpretation in a nontransplant center.