Low Grade Intraductal Carcinoma of Palate: An Extremely Rare Entity with Review of Literature.

Low-grade intraductal carcinoma (LG-IDC) is the new World Health Organization designation for tumors previously called "low-grade cribriform cystadenocarcinoma" and "low-grade salivary duct carcinoma". LG-IDC is a rare low grade malignant salivary gland neoplasm. A 56-year old woman presented with a painless swelling on the right posterior part of palate of 2 months duration. Radiographic examination revealed heterogenously enhancing soft tissue mass on right side of palate. A provisional diagnosis of pleomorphic adenoma was executed and local excision was done. The tumor had a typical feature of intraductal growth pattern composed of low grade ductal epithelial cells with cribriform and micropapillary patterns forming true "Roman bridges". Immunohistochemically myoepithelial cells displayed p63 around all tumor islands. The case was diagnosed as LG-IDC. LG-IDC is an extremely rare entity and awareness of this entity is important to avoid erroneous diagnosis and inappropriate treatment.