Accuracy of fine-needle aspiration cytology in the diagnosis of salivary gland masses according to the Milan reporting system and to an in-house system.

BACKGROUND: This study aims to assess in our institutional experience the accuracy of fine needle aspiration cytology (FNAC) in the diagnosis of salivary gland masses (SGM) according to the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) and to an in-house system. METHODS: The study included 189 FNACs conducted between January 2011 and December 2019. The FNACs, classified according to the in-house system, were reclassified according the MSRSGC. Taking histopathology as gold standard, the measures of diagnostic accuracy of FNAC were determined for suspicion for malignancy (SFM) and malignant categories. RESULTS: According to the in house system, FNAC diagnoses were classified as: 23 (12.2%) non-diagnostic (ND), 23 (12.2%) non-neoplastic (NN), 119 (62.9%) benign neoplasm (BN), 10 (5.2%) indefinite neoplasm (IN), 2 (1.1%) SFM, and 12 (6.4%) malignant (M). Based on the MSRSGC, there were 3 (1.5%) cases of atypia of undetermined significance (AUS) and 7 (3.7%) neoplasms of uncertain malignant potential (SUMP). The number of ND, NN, BN, SFM, and M cases were identical in the two systems. For both systems, the sensitivity, the specificity, the positive predictive value, the negative predictive value, and the accuracy for malignancy diagnosis were 77.8%, 100%, 100%, 97.6%, and 97.8%, respectively. CONCLUSION: According to the MSRGC and to our in-house reporting system, FNAC is an accurate technique for the diagnosis of malignant salivary tumors with excellent specificity and good sensitivity. However, MSRGC has the advantage of standardization of salivary gland cytology reporting.

Accuracy of fine-needle aspiration cytology of head and neck masses.

BACKGROUND: Head and neck masses are a common presentation in daily practice and can be challenging to both clinicians and cytopathologists. Fine needle aspiration cytology (FNAC) is a widely used method for the diagnosis of head and neck masses. The aim of the study was to assess our institutional experience of the accuracy of FNAC in the diagnosis of head and neck masses. METHODS: A total of 1262 FNACs were conducted from January 2013 to December 2016 and subdivided into benign and malignant categories. The thyroid and salivary glands FNACs were classified according to the Bethesda System for Reporting Thyroid cytopathology and to the Milan System for Reporting Salivary Gland Cytopathology respectively. The measures of diagnostic accuracy of FNAC were determined taking histology as a gold standard. RESULTS: A total of 7 false negative (FN) and 6 false positive (FP) FNACs were identified. Overall sensitivity and specificity of FNAC for a malignant diagnosis were 92% and 94.4%, respectively. Accuracy of FNACs of head and neck masses was 93.5% for all sites. The salivary gland group had the highest rate of FN (2.8%). All FP were reported in the thyroid group. These cases were cytologically classified suspicious for malignancy (n = 3) and papillary carcinoma (n = 3) and proved to be lymphocytic thyroiditis on final histology. Among the most common locations, cytology of lymph nodes provided the best sensitivity (98.2%). Salivary glands as well as lymph nodes had the best specificity (100%). CONCLUSION: FNAC of head and neck masses has a high accuracy allowing a correct therapeutic management. However, this accuracy depends on the anatomic location of the mass.