Pitfalls in Salivary Gland Fine-Needle Aspiration Cytology

Abstract

Introduction: Fine needle aspiration cytology (FNAC) of salivary gland lesion is being increasingly used. Major salivary
glands and some minor salivary glands are optimal targets for fine-needle aspiration (FNA). In some instances the final
histology of these lesions differs from the FNA result.
Objective: To determine the diagnostic accuracy of FNAC in salivary gland lesions and identify the salivary gland FNA
cases having discordant histological diagnosis so that most common diagnostic pitfalls can be avoided.
Material and Methods: In Pathology department, PIMS, 61 salivary gland FNAC cases from Jan 2008 to Sep 2009 were
retrospectively reviewed to identify the cytological characteristics that may have contributed to this discrepancy.
Results: 31 were males and age ranges from 04-76 years (mean 38.84 ± 14). 25(43.1%) were diagnosed non-neoplastic,
31(55.1%) were rendered benign while 02 (3.44%) were malignant on cytology. Positive predictive value of FNAC was
100% and negative predictive value was 91.4%. 08 FNAC cases show discordant diagnosis in specific typing of the lesion.
6/8 cases were misdiagnosed as pleomorphic adenoma. The most common missed diagnosis was mucoepidermoid carcinoma.
Conclusion: Pleomorphic adenoma and mucoepidermoid carcinoma are common in occurrence and create problems in
diagnosis. Experience cytopathologist should review all the cytology slides