Hyalinizing clear cell carcinoma of minor salivary glands: A case report with uncommon presentation.

Hyalinizing clear cell carcinoma (HCCC) is a rare malignant neoplasm that commonly arises in the palate, whose occurrence in other intraoral sites is extremely uncommon. We present a case of a 74 years old afro-descendant female presenting an asymptomatic swelling in the lingual region of teeth 32, 33 and 34, with four months of Evolution, promoting an area of bone resorption with imprecise margins. Incisional biopsy revealed proliferative nests of clear cells within a hyalinized fibrous connective tissue. Tumor cells showed immunohistochemical positivity for AE1/AE3, CK7, p63 and ki67 (30%), but negativity for CK14, CK19 and alpha-SMA. The final diagnosis was HCCC. The tumor was subjected to surgical resection and no recurrence was observed after 16 months. CCCH is a low-grade malignant tumor that must be differentiated from other malignant clear cell tumors, including epithelial-myoepithelial carcinoma, myoepithelial carcinoma, mucin-depleted mucoepidermoid carcinoma and metastatic renal clear cell carcinoma. Immunohistochemistry is a useful tool to achieve the correct diagnosis and provide the proper therapy for the tumor.