Hyalinizing clear cell carcinoma of the hard palate.

Hyalinizing clear cell carcinoma (HCCC) of the salivary gland is new disease only recognized in recent years. It is rare and the standard treatment is still under investigation. This is a report of a 42-year-old female with HCCC who presented with a painless submucosal hard palatal mass of three years duration. Wide excision of the tumour and the underlying palatal and maxillary bones was performed. Pathological examination revealed typical clear cells arranged in anastomosing trabeculae, cords, nests, or solid sheets with a hyalinizing stroma. These clear cells were positive for the periodic acid-Schiff (PAS) reaction but were negative for the mucin stain. Immunohistochemically, these neoplastic cells were positive for cytokeratin, but negative for actin. No recurrence nor distant metastasis was found during the eight-month follow-up period.