台耳醫誌

Herein, we report a case of Warthin-like mucoepidermoid carcinoma (WT-like MEC). In this case, histopathological examination revealed multiple cystic structures and a prominent lymphoid cell–rich stroma, resembling that of a Warthin tumor (WT)1 . However, the lesion lacked the characteristic well-organized bilayered oncocytic epithelium of WT and exhibited a rearrangement of the mastermind-like transcriptional coactivator 2 (MAML2) gene. Notably, the patient was significantly younger than typical patients with WT. WT-like MEC was then diagnosed on the basis of these pathological features and molecular findings, including fluorescence in situ hybridization findings. Surgical resection was performed, and no recurrence was observed during a 2-year follow-up. In conclusion, the detection of MAML2 rearrangement is crucial for accurate diagnosis. Therefore, MAML2 rearrangement testing is recommended in young, nonsmoking patients when WT is suspected to prevent misdiagnosis of WT-like MEC as benign WT2 . (J Taiwan Otolaryngol Head Neck Surg 2026; 60:53-61)