Infarction of basal cell adenoma of the parotid gland: First case report and literature review on CTNNB1 I35T mutations in salivary basal cell neoplasms.

Infarction has rarely been reported in some types of salivary gland tumors. In this study, we present the first case of infarction occurring in salivary basal cell adenoma. A 62-year-old male presented with swelling in the left parotid region. Histopathological examination revealed extensive central necrosis surrounded by a rim of viable tumor tissue showing the typical histology of basal cell adenoma. Nuclear β-catenin expression and the CTNNB1 p.I35T (c.104 T > C) mutation were identified in the tumor. A diagnosis of basal cell adenoma with central necrosis was made, and the postoperative period was uneventful. In addition, we review the literature on CTNNB1 I35T mutations in basal cell neoplasms of the salivary glands. Awareness of the possible occurrence of infarction and the high frequency of the unique mutation in basal cell adenoma may help in the differential diagnosis of salivary gland tumors.