Solitary fibrous tumor of the upper lip: Report of a pediatric case

Solitary fibrous tumor (SFT) is uncommon in the oral cavity, and there are no reports in children. We report a case of a large SFT affecting the upper lip of a one year-old boy. The tumor was characterized by proliferation of spindle and multinucleated stellate-shaped cells that were intermingled between thin and thick collagen fibers. The tumor cells were diffusely positive for CD34, Bcl-2, CD99, and negative for specific muscle actin, smooth muscle actin, calponin, and caldesmon. Ki-67 labeling was less than 1%. The patient remains well after tumor excision.