CLINICOPATHOLOGIC AND IMMUNOHISTOCHEMICAL FEATURES OF 2 CASES OF SOLITARY FIBROUS TUMOR OF THE ORAL CAVITY

Solitary fibrous tumor (SFT) is an uncommon soft tissue tumor that usually occurs in the pleura, but it is extremely rarely in the oral cavity. It presents an extensive microscopic diversity that may turn the diagnosis into a challenge. This is the report of 2 new cases of SFT in the buccal mucosa and tongue highlighting the clinical, microscopic, and immunohistochemical variations. The study included 2 women at 49 and 80 years old. Clinically, they were slow-growing, painless, small, well-defined submucosal masses. Microscopic examination showed well-circumscribed spindle cell proliferations associated with alternating dense hyalinization areas and characteristic stag horn-shaped blood vessels in variable arrangements. Immunohistochemistry showed consistently positivity for CD34 and vimentin, alternating positivity for Bcl-2 and epithelial membrane antigen and negativity for S-100. Patients are well with no recurrence or relapse.