The indeterminate categories of the Milan system for reporting salivary gland cytopathology (MRSGC): A minireview

Abstract

The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC), first published in 2018, attempted to develop a standardized and objective system of reporting salivary gland fine needle aspiration smears. It was widely accepted by the cytopathologists who started using it in their day-to-day practice. With the publication of new literature, the Milan system was updated and the 2 edition was released in 2023. The 5 WHO classification of salivary neoplasms, ancillary tests, and imaging characteristics of various salivary neoplasms have also been highlighted in the new edition. The 3 indeterminate categories of the Milan system of reporting are the atypia of undetermined significance (AUS), salivary gland tumor of undetermined malignant potential (SUMP), and suspicious for malignancy (SM) that create major dilemmas for the reporting cytopathologists. The present minireview highlights the criteria of diagnosis and further workup of the various lesions in these categories.