Mucoepidermoid carcinomas are composed of four cell types: mucin-producing, squamous, intermediate, and clear. Low-grade tumors are composed of cystic or gland-like spaces lined by mucinous cells admixed with epidermoid cells. The mucinous cells are goblet or balloon shaped with abundant foamy cytoplasm and small, dark peripherally placed nuclei. In some foci, they may be just admixed with solid clusters and nests of epidermoid cells. The cyst lining may be simple with one or more layers of cells or it may show complex cribriform and papillary architecture.