TACSTD2 and salivary duct carcinoma: In addition, 95.5% (21 out of 22) of adenoid cystic carcinomas, 95.7% (22 out of 23) of salivary duct carcinomas and 85.7% (6 out of 7) of epithelial myoepithelial carcinomas stained positive for Trop-2.