Myoepithelial carcinoma. Light micrograph (LM) of a section through a myoepithelial carcinoma. Myoepithelial carcinoma is a rare malignant (cancerous) tumour that usually occurs in the salivary glands in the mouth, but can also occur in skin and soft tissues. Approximately 66% of these tumours occur in a part of the salivary gland, known as the parotid gland. The average age of diagnosis is 55 years. Myoepithelial carcinoma consists almost entirely of myoepithelial cells with only the occasional duct-like structure. Magnification: x50 when printed at 10 centimetres wide.