Pleomorphic Adenoma
Pronunciation: plee-oh-MOR-fik AD-en-OH-muh
Also written as: PA — Pleomorphic Adenoma
The most common benign salivary gland tumour, characterised by diverse epithelial and mesenchymal-like elements within a single tumour mass, most frequently arising in the parotid gland.
Full Definition
Pleomorphic adenoma (PA) is a mixed tumour composed of epithelial (ductal and myoepithelial) cells embedded in a variable chondromyxoid stroma, accounting for approximately 60–70% of all salivary gland tumours. Although benign, it carries a risk of malignant transformation (carcinoma ex pleomorphic adenoma) if left untreated for extended periods. In oral medicine documentation, editors will most commonly encounter it in the context of intraoral minor salivary gland tumours of the palate. The term 'mixed tumour' is an older synonym that should be flagged when encountered in contemporary documents, as 'pleomorphic adenoma' is the standard current designation.
Usage
Usage note: The archaic synonym 'mixed tumour' should be updated to 'pleomorphic adenoma' in contemporary documents. When authors refer to 'carcinoma ex pleomorphic adenoma', this is a distinct malignant entity and must not be edited to 'pleomorphic adenoma'.
In Context
- "A well-defined, slowly enlarging swelling on the hard palate was excised and confirmed histologically as a pleomorphic adenoma of minor salivary gland origin." — Case report
- "Pleomorphic adenoma accounts for the majority of intraoral salivary gland tumours encountered in oral medicine practice." — Review article introduction