Accuracy of The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) in Fine needle aspiration of salivary gland

Abstract

BACKGROUND: The Milan system for reporting salivary gland cytopathology (MSRSGC) is a cytology reporting system, published in 2018 by the American Society of cytopathology (ASC) and the International Academy of Cytology (IAC).  The purpose is to evaluate sensitivity, specificity and accuracy of FNA interpretation between MSRSGC and conventional descriptive interpretation.

METHODS: Thirty-five cases from 74 cases presented with salivary mass had been performed FNA and surgical pathology diagnosis. The FNA microscopic slides of these 35 selected cases were reviewed and re-categorized into MSRSGC by three pathologists. MSRSGC was compared to conventional descriptive interpretation and surgical pathology diagnosis.

REESULT: From selected 35 cases, 23 cases (65.7%) were female, mean age was 50.6 years (SD 17.6). Eighty-five percent had mass which was greater than 2 cm in diameter. The accuracy, sensitivity and specificity of MSRGC were 91.43% (95% CI, 76.94-98.20), 90.3% (95%CI 74.2-98.0) and 100.0% (95%CI 39.8-100) respectively while the accuracy, sensitivity and specificity of conventional descriptive interpretation were 80.0% (95%CI 63.06 – 91.56), 80.6% (95%CI 62.5 – 92.5) and 75.0% (95%CI 19.4 – 99.4), respectively.

CONCLUSIONS: The MSRSGC is a useful method that can be used in reporting and categorizing cases preoperatively. Having a better understanding of the indeterminate diagnoses will help further refine risk classification criteria.