The Milan system for reporting salivary gland cytopathology and cyto-histological correlation with special emphasis on cystic lesions-4 years study in a tertiary care institute.

Abstract

Introduction: The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) was proposed by the American Society of Cytopathology and the International Academy of Cytology to bring uniformity in the reporting and treatment protocol. Cystic component is a common finding in non-neoplastic, benign and malignant lesions of the salivary gland. Fine needle aspiration is challenging in these cases due to pre-analytic error resulting in a high probability of false negativity.

Aim: To classify salivary gland lesions according to MSRSGC with special emphasis on cystic lesions and histological correlation.

Materials and methods: The study included 214 cases of salivary gland Fine needle aspiration cytology (FNACs) and classified according to MSRSGC with calculation of risk of malignancy (ROM) for each category.

Results: The most common age group affected was in the fourth - fifth decade (27.57%) and the common site was parotid gland. The majority of the cases belonged to the Milan category IVA (40.65%) and the least number in categories III and V (4.2%). Histopathology follow up was available in 50% of cases with the maximum number of surgery in category VI (78.5%). The highest ROM was for category VI (90.9%) followed by category V (83.3%). Cystic lesions constituted 22.64%, of which histopathological follow up was available in 64.58% of cases with a high ROM for category III and V(100%).

Conclusion: The ROM for cystic lesions is quite high for all categories as compared to the proposed MSRSGC. We suggest that repeat guided FNAC with a rapid on-site evaluation or ancillary diagnostic techniques can increase the diagnostic accuracy, especially for category I, III and cystic lesions.