Parotidectomy: a ten year experience with fine needle aspiration and frozen section biopsy correlation.

During the years 1980 through 1990, 247 patients underwent parotidectomy at our institution for the removal of primary parotid lesions. Charts were reviewed in an effort to document the distribution of pathology in patients undergoing parotidectomy and the histopathology from each case was organized and tallied by virtue of the final specific diagnoses. An additional goal of this study was to evaluate the efficacy of pre-operative fine-needle aspiration biopsy (FNAB) and frozen section pathology in accurately predicting final histopathology. In our series, 86.7% of lesions were found to be benign and 13.3% were malignant in nature. When compared to final pathologic findings, FNAB yielded a diagnostic accuracy rate of 89.3% with a 2.1% false negative rate with regards to pre-operative detection of malignancy. Frozen section biopsy was found to have a diagnostic accuracy of 94.1% and also demonstrated a 2.1% false-negative rate. We believe these studies are indeed complementary to each other, as reflected in the 96.2% diagnostic accuracy achieved with a combination of FNAB and frozen section biopsy information. This report will review the patterns of misdiagnosis for each modality of diagnostic testing and present the parotid histopathology found over a 10-year period.