Malignant salivary gland tumors

Malignant salivary gland tumors represent a heterogeneous group of rare tumors with distinct clinical, pathological and genetic features. Surgical resection often with adjuvant radio(chemo)therapy remains the first option of treatment while conventional chemotherapy has very little effect. Recent investigations focused on new insights into the genetic and histological characterization of tumors. For example new entities, such as mammary analogue secretory carcinoma were described. Moreover, high-grade transformations with dedifferentiation of the original tumor-specific malignant histology were found in several tumor types implicating aggressive tumor growth and worse prognosis. Etiopathogenetically, various subtypes, such as adenoid cystic carcinoma and mucoepidermoid carcinoma have specific chromosomal aberrations with formation of fusion genes which are responsible for driving cancer growth. Increasing knowledge of genomic alterations and tumor-specific signaling pathways provide promising evidence for molecularly targeted therapies in advanced tumor stages.