Epithelial-myoepithelial tumor of the bronchus.

A primary bronchial tumor with a histological pattern similar to that of epithelial-myoepithelial tumor of the salivary gland is reported in a 55-year-old woman. The tumor was well delimited, although not encapsulated, and showed a polypoid growth. The tumor was composed of two types of neoplastic cells: epithelial cells displaying tubules and myoepithelial cells that either formed compact masses or surrounded the tubular formations. Immunohistochemical study confirmed positive immunoreaction to both high- and low-molecular-weight cytokeratins in the epithelial cells and positive immunoreaction to vimentin, S-100 protein, and myosin in the myoepithelial cells.