Background: FNA is a cost-effective and minimally invasive diagnostic tool for sampling salivary gland lesions. However due to intra-tumoral heterogeneity and frequent overlapping of cyto-morphologic features precise subtyping of neoplasms can be challenging. To address this, International panel of experts under the joint effort of the American society of cytopathology and the International academy of cytology developed the MSRSGC.

Methodology: 356 salivary gland FNA samples were retrospectively analysed and re-categorised into 6 categories of the Milan system. Histopathology diagnoses were retrieved wherever available. Overall ROM were calculated for each category.

Results: On re-categorising into the Milan system, 62 cases were assigned to non-diagnostic category (17.4%), 67 to non-neoplastic category (18.8%), 48 as Atypical (13.5%), 101 as benign neoplasms (28.4%), 35 to the salivary gland neoplasm of uncertain malignant potential  (9.8%), 16 as suspicious for malignancy (4.5%) and 27 to the malignant category (7.6%).The ROM for above mentioned category were 30%, 7.1%, 14.2%, 3%, 31%, 67% and 95.2% respectively.

Conclusion: MSRSGC provides uniform reporting system for salivary gland cytopathology which helps to reduce reporting ambiguities and thus improves overall patient care.

Keywords:  Fine-needle aspiration; Milan system for reporting salivary gland cytopathology (MSRSGC); Risk of malignancy (ROM).

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Dr Roopashree G

Postgraduate Student, Department of Pathology, Mysore Medical College and Research Centre, Mysore