
Mucoepidermoid Carcinoma - Soft Palate
- Malignant epithelial salivary gland neoplasm - 10% of all salivary tumors, 30% of all salivary malignancies
- About 30% of these tumors arise from the minor salivary glands in the buccal mucosa and soft palate, the rest from major salivary glands
- Arises from ductal epithelium, has both epidermoid and mucinous components
- Appearance changes according to grade
- Low-grade lesions are well-circumscribed and inhomogeneous - may resemble pleomorphic adenoma
- High-grade lesions are invasive, ill-defined, with potential nodal involvement
- Will enhance on contrast-enhanced CT
- MR imaging shows a hypointense lesion on both T1 and T2 weighting
- Late recurrence is common - follow-up is necessary for at least ten years following resection
- Radiation exposure is a known risk-factor
- Contains epidermal growth factor receptor (EGFR), which is overexpressed in approximately 2/3 of the cases.
- This is contrasted with HER2+ which is expressed in less than 5%. Herceptin appears to have low activity even among the HER2+ cases.
References:
1. Taxy, J. "Pathology of head and neck neoplasms" Up to Date. Mar 26, 2018.