Pathology and Diagnosis
- Myoepithelial cells can be spindled, plasmacytoid, epithelioid, or clear.
- Tubules or epithelium are absent or present in a small amount (5%) by definition.
- Tumors with myoepithelial cells and a large amount of tubules are classified as pleomorphic adenomas.
- Pleomorphic adenomas must contain the characteristic chondromyxoid stroma, which is normally absent in myoepithelioma.
- The absence of tubules and chondromyxoid stroma helps differentiate myoepithelioma from pleomorphic adenoma.
- Myoepitheliomas are diagnosed through examination of the tissue by a pathologist.
- Diagnosis can be confirmed through low magnification examination.
- High magnification examination may be necessary for accurate diagnosis.
- Histopathological features specific to myoepithelioma aid in diagnosis.
- Immunohistochemical staining can be used to support the diagnosis.
Treatment
- Benign myoepitheliomas are treated with simple excision.
- They have a lower recurrence rate compared to pleomorphic adenomas.
- Malignant myoepitheliomas are also excised.
- In the past, dacarbazine has been used for treatment of malignant myoepitheliomas.
- Malignant myoepitheliomas are prone to both metastasis and recurrence.
Related Entities
- Pleomorphic adenoma is closely related to myoepithelioma.
- Ectomesenchymal chondromyxoid tumor is another related entity.
- Both pleomorphic adenoma and ectomesenchymal chondromyxoid tumor have distinct features distinguishing them from myoepithelioma.
- Understanding these related entities helps in accurate diagnosis.
- Comparative analysis of these entities contributes to the understanding of their pathogenesis.
References
- Barnes, L., Appel, BN., Perez, H., El-Attar, AM. (Jan 1985). Myoepithelioma of the head and neck: case report and review. Journal of Surgical Oncology, 28(1), 21–8.
- Wu, Tao; Lao, Zhiwei; Tang, Jun (1 January 2014). Myoepithelial carcinoma of the head and neck: A report of 23 cases and literature review. Cancer Treatment Communications, 2(2–3), 24–29.
- Smith BC, Ellis GL, Meis-Kindblom JM, Williams SB (May 1995). Ectomesenchymal chondromyxoid tumor of the anterior tongue. Nineteen cases of a new clinicopathologic entity. American Journal of Surgical Pathology, 19(5), 519–30.
- These references provide further insights into the characteristics, diagnosis, and treatment of myoepithelioma.
- They contribute to the existing literature and research on this topic.
Notable Points
- Pleomorphic adenomas must contain the characteristic chondromyxoid stroma, which is normally absent in myoepithelioma.
- Myoepitheliomas have a lower recurrence rate compared to pleomorphic adenomas.
- Malignant myoepitheliomas are prone to both metastasis and recurrence.
Myoepithelioma of the head and neck, also myoepithelioma, is a salivary gland tumour of the head and neck that is usually benign. When malignant, which is exceedingly rare, they are known as malignant myoepithelioma or Myoepithelial carcinoma, and they account for 1% of the salivary tumors with poor prognosis.
| Myoepithelioma of the head and neck | |
|---|---|
 | |
| Micrograph of a myoepithelioma. H&E stain. | |
| Specialty | Oncology |
| Types | Benign, Malignant (rarely) |
As the name suggests, it consists of myoepithelial cells. Classically, they are found in the parotid gland or palate. A similar tumor type may be found in the tongue, referred to as ectomesenchymal chondromyxoid tumor.
