Pathologic Discordance in Skull Base Tumors

Abstract

Objectives:

A wide range of pathologies cause skull base tumors, which require accurate diagnosis for appropriate treatment. These lesions can be difficult to biopsy in the clinic due to patient intolerance and risk of bleeding, and in the operating room due to difficulty with access. The objective of this study was to analyze diagnostic accuracy among patients with skull base tumors referred to a tertiary care center.

Methods:

We retrospectively reviewed the records of patients referred to the University of Michigan Multidisciplinary Cranial Base program over a 2 year period (July 2010-June 2012). We excluded patients referred for pituitary lesions, for internal auditory canal/cerebello-pontine angle lesions, and without concern for tumors (encephaloceoles, CSF leaks, fractures). We collected data regarding biopsy prior to referral, histologic diagnosis by outside pathologists, diagnosis on review by University of Michigan pathologists, and final histologic diagnosis after repeat biopsy, resection, or both.

Results:

The records of 177 patients were reviewed. Fifty-nine (59) patients had specimens which had been reviewed by both community pathologists and University of Michigan pathologists. There was some discrepancy in histologic diagnosis in 17/59 (28.8%) of the patients. The most frequent diagnosis with discordance was squamous cell carcinoma (5/17, 29%) and sinonasal undifferentiated carcinoma (2/17, 11.8%). No patient’s diagnosis was changed from benign to malignant or vice-versa.

Conclusions:

There is a high rate of discrepancy (28.8%) in the diagnosis of skull base tumors when reviewed by community pathologists compared to specialized pathologists at a tertiary care institution.