Background:
The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) was first published in 2018 with the aim to provide an international standardised, evidence-based reporting protocol for salivary gland fine needle aspirates (FNAs) and allow clear communication between pathologists and clinicians to improve patient care.
Aim:
We evaluated the use of the MSRSGC in the reporting of salivary gland FNAs in St. James’s Hospital (SJH), compared the cytology and histology diagnoses where available, calculated Risk of Malignancy (ROM) and examined discordant cases.
Method:
Retrospective search using Telepath and Electronic Patients Records in SJH was carried out over the course of 18 months from 01-01-2022 to 30-06-2023 on all salivary gland FNAs. Each case was categorised according to MSRSGC guidelines and ROM was calculated for each category.
Results:
There were 151 salivary gland FNAs during the period, characterized as: nondiagnostic (ND) 39 (26%), non-neoplastic (NN) 26 (17%), atypical cytology (AC) 8 (5%), benign neoplasm (BN) 54 (36%), salivary gland of uncertain malignant potential (SUMP) 11 (7%) and malignant (M) 13 (9%).
Histopathological follow up was available for 42/151 (27.8%) specimens; where cytology histology concordance was seen in 39/42 cases (92.9%). The remaining 3 (7.1%) discordant cases were categorised as 2 NN and 1 SUMP on cytology.
The ROM for each MSRSGC category was calculated as- ND 50%, NN 33%, AC 100%, BN 0%, SUMP 44% and M 100%.
Conclusion:
MSRSGC category number has been regularly used on cytology reports after its introduction in SJH. Cytology histology concordance is good; although ROM is higher as compared to other studies. Discordant cases will be reviewed and learning points will be discussed.
Niamh Mooney1, Christopher Mulvey1, Siobhan Nicholson1, Bijal Shah1
1 Department of Histopathology, St. James’s Hospital, Dublin