Cytohistological correlation and risk stratification of salivary gland lesions using the Milan System for Reporting Salivary Gland Cytopathology: A tertiary care centre experience

Introduction Salivary gland neoplasms account for approximately 5% of head and neck tumours. The cytomorphology of fine needle aspiration material helps determine the preoperative assessment and risk stratification. The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) was developed to improve communication between the laboratory and treatment provider. Aims and objective In the present study, we stratified all salivary gland lesions according to the MSRSGC and evaluated each category's concordance and risk of malignancy (ROM). Materials and methods This was a 5 year retrospective study. First, all cases were assigned to one of the six MSRSGC categories. Then, following cytohistological correlation, the concordance rates and ROM were calculated based on the final histopathology report. Results A total of 354 cases were identified, with ages ranging from 2 to 88 years and the commonest age group was the 3rd to 4th decades. Categories I, II, III, IVA, IVB, V, and VI comprised 5.37% (19/354), 26.84% (95/354), 1.13% (04/354), 51.41% (182/354), 1.98% (07/354), 1.13% (04/354), and 12.15% (43/354) of the cases, respectively. The overall concordance rate between the cytological and histopathological diagnoses was 81.25% (65 out of 80 cases), with the sensitivity, specificity, positive predictive value, and negative predictive value at 43.48%, 96.49%, 83.33%, and 80.88%, respectively. Conclusion The MSRSGC provides a better objective and structured way to communicate with the health care provider. In our study, the overall concordance rate was observed in 62/80 cases, with maximum concordance seen in categories III, IVB, and V of the MSRSGC. The Milan System for Reporting Salivary Gland Cytopathology is developed to better communicate between the laboratory and treatment provider. The overall concordance rate between the cytological and the histopathological diagnosis was 81.25%, with sensitivity, specificity, positive predictive value, and negative predictive value at 43.48%, 96.49%, 83.33%, and 80.88%, respectively.