Result of Reporting Cytology of Salivary Gland According to Milan System in Five-year Achieves of Rajavithi Hospital

Abstract

Background: The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) is a reporting system for Fine-needle aspiration cytology (FNAC) to diagnose and manage salivary gland tumors. MSRSGC is a six-tier classification that provides a standardized terminology and ROM for each category, thus avoiding ambiguity in FNAC interpretation.Objective: The present study was conducted to evaluate the risk of malignancy by applying the Milan system to diagnose salivary gland lesions in the institute.Method: The study was a retrospective study for risk of malignancy with cytohistological correlation by applying Milan System in the department of pathology at Rajavithi hospital for five years. The salivary gland FNAC cases were reviewed and divided into six categories per the proposed Milan system for reporting salivary gland cytopathology. The cases with available histopathology were further consolidated according to the proposed Milan system, and the risk of malignancy were calculated.Results: The number of cases in each category was Non- diagnostic 26.4%, Non-neoplastic 20.6%, AUS 6.5%, Benign neoplasm 34.7%, salivary lesions of uncertain malignant potential (SUMP) 14.1%, Suspicious for malignancy 11.9%, and malignant neoplasm 11.9%. The risk of malignancy for each category was 15.8% (Non- neoplastic), 33.3% (AUS), 12.5% (Benign neoplasm), 53.8% (SUMP), 90.9% (Suspicious for malignancy), and 90.9% (Malignant neoplasm).Conclusion: MSRSGC is a useful system for risk assessment. It is an effective protocol to differentiate benign from malignant tumors, especially for categories V and VI. Our findings also suggest that in addition to the surgical follow-up, the inclusion of the clinical and radiological follow-up may be a better strategy for the calculation of risk of malignancy, especially for categories IVB (SUMP).