2020 Volume 59 Issue 1 Pages 38-46
Objective : The aim of this study was to elucidate the potential diagnostic usefulness of the Milan system for fine needle aspiration cytology (FNAC) of salivary gland lesions.
Study Design : A prospective analysis was conducted of 89 cases of salivary gland FNAC specimens obtained in 2018. The risk of malignancy (ROM) was calculated in the 48 cases for which histological confirmation was available.
Results : The frequency, ROM and histological malignancies in each category were as follows ; Non-diagnostic, 14.6% (n=13), ROM 25% (1/4 cases ; low-grade mucoepidermoid carcinoma) ; Non-neoplastic, 14.6% (n=13), ROM 33.3% (1/3 cases ; T-zone lymphoma) ; Atypia of undetermined significance (AUS), 20.2% (n=18), ROM 30% (3/10 cases ; follicular lymphoma, adenoid cystic carcinoma[ADCC], salivary duct carcinoma[SDC]) ; Neoplasm, benign 30.3% (n=27), ROM 5.9% (1/17 cases ; ADCC) ; Salivary gland neoplasm of uncertain malignant potential (SUMP), 7.9% (n=7), ROM 40% (2/5 cases ; ADCC, epithelial-myoepithelial carcinoma) : Suspicious for malignancy 2.2% (n=2), ROM 100% (2/2 cases ; follicular lymphoma, carcinoma ex pleomorphic adenoma[CXPA]) ; Malignant 10.1% (n=9), ROM 100% (7/7 cases ; metastatic cancer 3, SDC/CXPA 2, acinic cell carcinoma 1, ADCC 1). The diagnostic accuracy was 93.1%, but pitfall was present in there were the pitfalls of inadequate specimens and lymph node lesions.
Conclusion : The Milan system seems useful for salivary FNAC, especially in cases where cytological differentiation between non-neoplastic and neoplastic lesion or between benign and malignant lesions is difficult.
