Abstract: Mucoepidermoid carcinoma (MEC) is the most common malignant tumor of salivary gland origin in children and young adults, with a male-to-female ratio of approximately 3∶2. Classical MEC consists of mucous cells, epidermoid cells, and mesenchymal cells in various proportions, and there are some rare subtypes in addition to the classical three cellular components, among which, the clear-cell subtype is the one in which the percentage of clear cells in the tumor exceeds that of the other three classic cellular components. In terms of molecular genetics, most mucoepidermoid carcinomas have a CRTC1/MAML2 gene fusion. In this article, we report a case of clear cell type moderately differentiated mucoepidermoid carcinoma occurring in the palatal mucosa of a child, in order to improve the diagnostic ability of this type of disease in the future, and to reduce the occurrence of misdiagnosis and underdiagnosis.

Key words: mucoepidermoid carcinoma, clear cell subtype, clinicopathology, differential diagnosis