Abstract
We report a rare case of a solitary fibrous tumor (SFT) forming a small mass in the floor of the mouth. SFT is an uncommon spindle cell neoplasm of mesenchymal origin. It belongs to intermediate (rarely metastasize) tumors of fibroblastic/myofibroblastic tumors in the WHO classification of soft tissue tumors. Although it occurs mainly in the pleura and has been found at ubiquitous sites, SFT in the oral cavity, especially the floor of the mouth, is still considered uncommon.
A 57-year-old woman developed a 7-mm painless mobile irregular round mass with an uneven surface in the center of the floor of the mouth. The tumor was diagnosed clinically as a salivary gland tumor of the left floor of the mouth or granuloma, and was totally resected. The surgical specimen consisted of fibroblastic spindle cells and collagen fiber. Tumor cells were immunoreactive for CD34 and Bcl-2 and negative for SMA, desmin, S-100, CD99 and c-kit. The tumor was histopathologically diagnosed as SFT.
There has been no sign of recurrence or metastasis for 19 months since the resection.
