Cytopathological spectrum of salivary gland lesions and classification according to the MILAN system

Abstract

Background: Fine needle aspiration cytology (FNAC) is a minimally invasive useful  procedure for  evaluating lesions of salivary glands  all over the world. Diverse morphological patterns in salivary gland lesions make diagnosis challenging at times hence Milan system of reporting was introduced to overcome this difficulty.

Method: This is a two year retrospective and one year prospective study from January 2021 to January  2024 conducted on 73 cases of salivary gland lesions. Smears were stained with May-Grünwald Giemsa stain, Haematoxylin and Eosin and Papanicolaou stains. Smears of old  cases were retrieved from records and were classified according to Milan system of reporting sal̥ivary gland cytology.Histopathological comparison was done wherever possible and sensitivity, specificity, positive predictive value, negative predictive value , diagnostic accuracy of FNAC for diagnosing benign and malignant lesions and risk of malignancy for each category was calculated.

Result:  73 salivary gland lesions were included in the study with most common age group being 31-40 years (23.28%) and male to female ratio of 1.8:1. Acute sialadenitis (13.7%) was the most common non-neoplastic lesion and Pleomorphic adenoma (34.24%) was the most common benign lesion. The commonest malignancy was mucoepidermoid carcinoma (4.11%). Histopathology was received for 19 cases. Statistical analysis revealed the Sensitivity, Specificity, Positive predictive value, Negative predictive value and Diagnostic accuracy as 75% ,100%, 100%, 93.75% and 94.73% respectively.

Conclusion: FNAC is a simple and cost-effective procedure with high sensitivity ,specificity and accuracy which makes it a reliable diagnostic tool for rapid and early diagnosis of salivary gland lesions.

Keywords : Salivary gland lesions, Pleomorphic adenoma, Mucoepidermoid carcinoma, Milan system .