Primary clear cell carcinoma of minor salivary gland of the soft palate: a case report

Clear cells can be found in numerous salivary and non-salivary tumors in the head and neck region, including metastatic lesions. They are rare low-grade tumors accounting for less than 1% of all salivary gland tumors and occur almost exclusively in the intra-oral minor salivary glands. Hyalinizing clear cell carcinoma (HCCC) is an extremely rare and recently described neoplasm predominantly affecting the oral cavity. Histologically, it is characterized by nests of glycogen-rich monomorphic clear cells within a hyaline stroma. HCCC often follows an indolent course with a limited metastatic potential. It is therefore important to differentiate this entity from other more aggressive clear cell tumors including metastatic tumors such as renal cell carcinoma. We hereby report a case of HCCC localized in minor salivary glands specifically in soft palate for its rarity, as well as to discuss the role of immunohistochemical stains, essential for its definitive diagnosis.