A 48-year-old woman presents with a painless, slowly enlarging parotid mass. FNAC shows a mixture of squamous cells, mucin-secreting cells, and intermediate cells. Which is the most likely diagnosis?
- A Pleomorphic adenoma
- B Mucoepidermoid carcinoma ✓
- C Adenoid cystic carcinoma
- D Acinic cell carcinoma
Correct answer: B. Mucoepidermoid carcinoma
Explanation
Mucoepidermoid carcinoma is the most common malignant tumour of the parotid gland and shows a characteristic mixture of epidermoid, mucinous, and intermediate cells on cytology and histology. It is associated with a MECT1-MAML2 fusion from t(11;19). Pleomorphic adenoma shows epithelial cells in chondromyxoid stroma without squamous-mucinous mixtures, and adenoid cystic carcinoma shows basaloid cells in cribriform patterns, which kills both distractors.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.