Pleomorphic Adenoma
Lester D. R. Thompson, MD
Key Facts
Terminology
Benign, epithelial-derived neoplasm whose cells demonstrate both epithelial and mesenchymal differentiation
Macroscopic Features
Develop from mucosa of bony or cartilaginous nasal septum
Mucosa-covered, firm, polypoid mass
Microscopic Pathology
Unencapsulated, highly cellular tumors
Myoepithelial cells with plasmacytoid appearance usually predominate
Scant myxochondroid matrix material
Ancillary Tests
Epithelial and myoepithelial reactions with keratins, GFAP, S100 protein, Actin-sm, p63
 Hematoxylin & eosin shows an intact respiratory epithelium  overlying a cellular pleomorphic adenoma with a predominantly glandular pattern. |
 Hematoxylin & eosin shows myxoid matrix material with associated epithelial neoplasm. The epithelium shows gland-duct formation as well as ribbons and strips of epithelium. |
TERMINOLOGY
Abbreviations
Pleomorphic adenoma (PA)
Synonyms
Benign mixed tumor (BMT), intranasal mixed tumor, nasal blastoma, mixed salivary tumor, chondroid syringoma
Definitions
Benign, epithelial-derived neoplasm whose cells demonstrate both epithelial and mesenchymal differentiation
CLINICAL ISSUES
Epidemiology
Incidence
Rare, although comprises ˜ 25% of all sinonasal tract glandular neoplasms
Age
Usually between 20 and 60 years (mean: 40 years)
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
