Author(s)
                                                Susannah Orzell MD MPH
                                                
Yesha Sheth MD
Jesse Ryan MD
                                                Affiliation(s)
                                                SUNY Upstate Medical University
                                                Abstract:
                                                Educational Objective: At the conclusion of this presentation, the participants should be able to describe the typical clinical, radiographic and histopathologic findings for a solitary fibrous tumor. They should also be aware that STAT-6 positivity is highly sensitive and specific for the diagnosis of a solitary fibrous tumor but not pathognomonic.  Objectives: Discuss the presentation, histology and immunohistochemical characteristics of solitary fibrous tumors.  Study Design: Case report and literature review.  Methods: A retrospective chart review was performed on a 54 year old female who had presented with a midline mobile, nontender neck mass. She underwent an FNA followed by an uneventful excision of the mass. Radiology, pathology and histology were reviewed. A PubMed search was performed for the literature review.  Results: Histology was consistent with a solitary fibrous tumor, and this was supported by bcl-2, CD34 and CD99 positivity, as well as S-100 and EMA negativity. STAT-6, which has been shown to be highly predictive of solitary fibrous tumors, was negative in this patient.  Conclusions: Although STAT-6 has been shown to be highly predictive of solitary fibrous tumors, it is not diagnostic, as demonstrated in this case report. The diagnosis of a solitary fibrous tumor was made based on histology and results of other immunohistochemical testing.