Oncocytic/oncocytoid lesions are a distinct group of salivary gland diseases. Proposed in 2023 The Milano Salivary Gland Cytology Reporting System clearly states that oncocytic/oncocytoid salivary gland lesions cannot be effectively differentiated by conventional cytology into non-neoplastic lesions and benign and malignant lesions. Thus, most lesions lacking classic cytomorphologic features would be classified under the general diagnostic term «Salivary gland neoplasm of undetermined malignant potential» (SUMP).
OBJECTIVE
To determine differential diagnostic clinical, radiological, cytological, immunocytochemical and molecular genetic signs for various oncocytic/oncocytoid lesions of the salivary glands.
MATERIAL AND METHODS
A total of 463 patients with pathology of the salivary glands were comprehensively examined, of which 41 patients were diagnosed with oncocytic/oncocytoid lesions of the salivary gland.
All patients underwent cytological, immunocytochemical, and molecular genetic studies. Immunocytochemistry and molecular genetic studies were carried out on cell blocks.
RESULTS
Differential diagnostic clinical, radiological, cytological, immunocytochemical and molecular genetic signs have been identified for various oncocytic/oncocytoid lesions of the salivary glands: Warthin’s tumor, oncocytoma, nodular oncocytic hyperplasia (oncocytosis), myoepithelioma, mucoepidermoid carcinoma, acinar cell carcinoma, secretory carcinoma, epithelial myoepithelial carcinoma, ductal carcinoma, clear cell carcinoma, metastasis of renal cell clear cell carcinoma, metastasis of squamous cell carcinoma.
CONCLUSION
The developed morphological, immunophenotypic and molecular genetic signs of oncocytic/oncocytoid lesions of the salivary gland made it possible to reduce the number of uncertain diagnoses from 8.9% to 3.9% of cases.