UC Irvine

Solitary fibrous tumor (SFT) is an uncommon spindle cell neoplasm of increasing incidence that was originally described to be of pleural origin; however, more recently, SFT has been reported in extrapleural sites, including the orbit, liver, salivary glands, tongue, nose, paranasal sinuses, larynx, retroperitoneum, meninges, and thyroid. The increase in the number of SFTs does not necessarily mean increased incidence of this tumor but rather an increased understanding of this tumor, especially recognition of this tumor in extrapleural locations, which has been aided by immunohistochemical analysis. We report a case of SFT in the auditory canal, which to our knowledge has not been previously reported, as evident by morphologic findings and immunophenotype.