A carcinoma that arises from a pleomorphic adenoma in the salivary glands. It usually originates in the parotid gland. Patients usually present with a history of a long-standing tumor mass which grew rapidly in the past few months. Patients with non-invasive or minimally invasive carcinoma have an excellent prognosis. In cases where there is invasion of the surrounding tissues, the clinical course is aggressive. [from
NCI]