Hyalinizing Clear Cell Carcinoma of the Salivary Gland in an Elderly Female: A Case Report Supported by EWSR1 Molecular Studies.

Hyalinizing clear cell carcinoma of the salivary gland is a rare neoplasm, accounting for only less than 1% of malignancies arising from the salivary gland. It is molecularly defined by the expression of the EWSR-ATF1 fusion oncogene. To date, there has been no previous studies published yet in the Philippines regarding the existence of this tumor. In this paper, we present a case of a 70-year-old elderly female who had a 10-year history of a gradually enlarging left lateral neck mass. Histopathologic examination showed a tumor arranged of cords, nests, and trabeculae of monomorphic round cells with abundant clear to lightly eosinophilic cytoplasm surrounded by thick hyalinized collagen bundles. Immunohistochemistry and molecular studies were done which revealed a positive p63 staining, negative SMA and S100, and an EWSR1 rearrangement in Fluorescence in situ hybridization (FISH), thus, confirming the diagnosis.