Mucoepidermoid carcinoma

Presents as painless, slow-growing mass that is firm or hard. Most appear clinically as mixed tumors. Usually occurs at 30–50 years of age. More predilection towards female sex. ==Diagnosis==

Histology This tumor is not encapsulated and is characterized by squamous cells, mucus-secreting cells, and intermediate cells. Image:Mucoepidermoid carcinoma (2) HE stain.jpg|Histopathologic image of mucoepidermoid carcinoma of the major salivary gland. H & E stain Image:Mucoepidermoid carcinoma (3) HE stain.jpg|Histopathologic image of mucoepidermoid carcinoma of the major salivary gland. The same lesion as shown in a filename "Mucoepidermoid carcinoma (2) HE stain.jpg". H & E stain Image:Mucoepidermoid carcinoma (1) AB-PAS stain.jpg|Histopathologic image of mucoepidermoid carcinoma. Postoperative recurrence of the submandibular tumor. Alcian blue-PAS stain Molecular biology Mucoepidermoid carcinomas of the salivary and bronchial glands are characterized by a recurrent t(11;19)(q21;p13) chromosomal translocation resulting in a MECT1-MAML2 fusion gene. The CREB-binding domain of the CREB coactivator MECT1 (also known as CRTC1, TORC1 or WAMTP1) is fused to the transactivation domain of the Notch coactivator MAML2. A possible association with radiation exposure has been reported. It has also been proposed that mucoepidermoid tumors arise from subepithelial mucous glands of the upper respiratory or digestive tracts. == Prognosis ==

Generally, there is a good prognosis for low-grade tumors, and a poor prognosis for high-grade tumors, however recent research have found reoccurring low grade tumors also have a poor prognosis. ==Treatment==

Surgery is the recommended treatment for localised resectable disease. When the tumour is incompletely resected (positive margins) post-operative radiotherapy gives local control comparable to a complete resection (clear margins). Sometimes when surgery is not possible due to extent of disease or if a patient is too frail for surgery, or declines surgery, palliative radiotherapy may be helpful. There has been a report of a case where low dose radiotherapy achieve disease response and control for more than 4 years. In patients with metastatic disease, chemotherapy response tends to be low (27% partial response rate) and short lived. ==Epidemiology==

Occurs in adults, with peak incidence from 20–40 years of age. A causal link with cytomegalovirus (CMV) has been strongly implicated in a 2011 research. File:Relative incidence of parotid tumors.png|Relative incidence of parotid tumors, showing mucoepidermoid carcinoma at top right. File:Relative incidence of submandibular tumors.png|Relative incidence of submandibular tumors, showing mucoepidermoid carcinoma at top right. == References ==