POLYMORPHOUS ADENOCARCINOMA WITH PAPILLARY AND CRIBRIFORM PATTERNS

Polymorphous adenocarcinoma (PAC) is the second most common intraoral malignant salivary gland tumor. Although generally considered a low-grade tumor, when presenting a cribriform or papillary configuration there is a poorer prognosis. We report 2 PAC cases. Case 1: A 35-year-old man presented a pediculated nodule with reddish areas. Case 2: A 67-year-old woman presented with sessile nodule exhibiting telangiectatic areas. Both lesions occurred in the left hard palate, had smooth surface, measured approximately 3 cm, were painless, and at had least 4 years of evolution. Microscopically, both showed round isomorphic cells with indistinct cytoplasmic outlines and ovoid nuclei. Architectural pattern showed solid sheets, single files of cells, ducts with 1 cell layer, and papillary cystic formations. Perineural and minor salivary glands invasion were observed. The stroma is variably hyalinized and myxoid. In case 2, cribriform structures were also observed, indicating a higher probability of metastasis.