The value of fine needle aspiration cytology in the clinical management of rare salivary gland tumors

Abstract

Salivary gland tumors are relatively rare neoplasms, mostly located in the parotid gland, and few are malignant. Preoperative evaluation of salivary gland tumors includes fine needle aspiration cytology (FNAC).ObjectiveThe purpose of this study was to determine the importance of FNAC in the evaluation of rare salivary gland neoplasms.Material and MethodsFour cases of rare salivary gland tumors were included, which were preoperatively assessed by clinical investigation, computed tomography, and FNAC.ResultsThe presented cases include myoepithelial carcinoma, oncocytic carcinoma, undifferentiated lymphoepithelial carcinoma, and marginal zone lymphoma.ConclusionFNAC is a reliable diagnostic tool for common salivary gland neoplasms; however, rare tumors often represent diagnostic challenges.Clinical relevanceIn such rare tumors, the role of aspiration cytology may be limited to establishing the dignity of the lesion (benign/malignant). This knowledge enables the surgeon to choose the most appropriate therapeutic procedure. A definitive diagnosis of rare tumors (either epithelial or nonepithelial) is obtained by histological examination; cytology is limited in this regard due to overlapping features.

The key radiologic and cytomorphologic features of oncocytic and oncocytoid lesions of the salivary gland

“…Cytologic smears are generally cellular and show crowded groups of large, polygonal cells with abundant granular cytoplasm, sharp contours, round to oval nuclei and even chromatin(Figure ). The cells may be slightly discohesive, leading to smaller groups and some single cells . Moderate to marked nuclear atypia may be seen, including hyperchromasia, anisonucleosis, nuclear membrane irregularities, multiple nuclei and prominent nucleoli, but these features are variably present and not always appreciated on the basis of cytology alone, making accurate diagnosis difficult at times …”

“…The cells may be slightly discohesive, leading to smaller groups and some single cells. 138 Moderate to marked nuclear atypia may be seen, including hyperchromasia, anisonucleosis, nuclear membrane irregularities, multiple nuclei and prominent nucleoli, but these features are variably present and not always appreciated on the basis of cytology alone, making accurate diagnosis difficult at times. 131,137 The differential for OC on FNAC includes WT, oncocytoma, and nodular oncocytic hyperplasia (NOH).…”

Incorporation of the Milan system in reporting salivary gland fine needle aspiration cytology—An insight into its value addition to the conventional system

“…This is attributable to significant cytomorphologic diversity and overlap between reactive and neoplastic lesions encountered in the salivary glands. The diversity of the histological subtypes (ductal, acinar, myoepithelial and basal cell types) and the overlapping morphology of lesions add to the difficulty . In many cases a specific diagnosis cannot be achieved and descriptive reports are given.…”

Diagnostic value of preoperative fine needle aspiration cytology in parotid gland tumors

“…Clinical studies have shown that the aspiration cytology of salivary gland tumors has a sensitivity of 60% to 100% and a specificity of 90% to 100%. 10 In some published studies, it is argued that FNAC is unnecessary due to low sensitivity and high false negativity and the localization of the lesion is the most important determinant of surgical operation. 11 In the present study, the specificity of fine needle aspiration cytologies that we diagnosed was 98%, sensitivity was 90%, positive predictive value was 86%, negative predictive value was 98%, and accuracy was 97%.…”

“…This classification scheme is comprised of seven diagnostic categories, including nondiagnostic, benign nonneoplastic, atypia of undetermined significance, benign neoplasm, salivary gland neoplasm of uncertain malignant potential, suspicious for malignancy, and malignant. 10 After FNAC smears were examined and diagnosed, samples taken from surgical specimens of these cases and routinely stained with HE were re-evaluated and diagnosed.…”