Details
28 year-old woman with left parotid mass.
Pleomorphic adenoma is the most common neoplasm of salivary gland origin. It most frequently arises in the parotid gland; the minor salivary glands are the second-most frequently affected sites. It usually occurs in women in their 30s, but can also occur in other age groups. Clinically, they present as a painless, mobile, slow-growing mass.
Histologically, pleomorphic adenomas consist of biphasic populations of epithelial and mesenchymal components. The epithelial component shows variable morphology of glandular or occasionally squamous, spindle, clear plasmacytoid or basaloid cells. The mesenchymal component consists of myxoid, hyaline, or chondromyxoid stroma. Rarely, adipose or calcified bone can be seen.
Treatment of these tumours consist of wide, local excision with overall risk of recurrence of ≤ 2.5% within 10 years. The risk of malignant transformation is up to 10%, with the following risk factors: male gender, older age (> 40 years), larger size (> 2 cm), parotid gland involvement, recurrent tumours, and long-standing untreated tumours.