Disease Definition: Solitary fibrous tumor (SFT), also known as fibrous tumor of the pleura, is a rare mesenchymal tumor originating in the pleura or at virtually any site in the soft tissue including seminal vesicle. Approximately 78% to 88% of SFT's are benign and 12% to 22% are malignant. It is a heterogeneous group of rare spindle-cell tumors that include benign and malignant neoplasms. Their cell of origin is still debated. SFT is preferred by most pathologists as a better term than “hemangiopericytoma” that gathers numerous unrelated entities and is presently only employed by neuropathologists. We focus the present paper on the forms of this family of tumors occurring in adult patients. There are 3 typical primary locations: pleural, meningeal and extrathoracic soft tissue.
Disease Symptoms: Patients present with proptosis and possibly ptosis, eyelid swelling, tearing, diplopia or decreased vision. Malignant infiltrating lesions can sometimes cause pain.
Disease Treatment: Because even benign-appearing solitary fibrous tumors (SFTs) can be locally recurrent and metastatic, wide resection of both benign and malignant SFTs is recommended. Preoperative vascular studies and arterial embolization should be considered because of the known bleeding risk with resection. Careful exclusion of other diagnoses (eg, synovial sarcoma) is important. Because of the favorable outcome with SFTs, it may be possible to avoid limb-threatening and deforming operations. No evidence suggests that adjuvant chemotherapy is beneficial. If the SFTR appears malignant histologically, adjuvant radiation therapy may be considered. Long-term follow-up is recommended because local and distant relapse is possible, even with benign-appearing tumors.
Statistics: 42 patients (20 males) with SFTP (median (IQR) age 62 (56–71) years) could be identified. SFTP were associated with symptoms in 50% of all cases. Complete resection was achieved by video-assisted thoracic surgery or thoracotomy in 20 and 22 patients, respectively. Three SFTP-related deaths (7.1%) and four tumor recurrences (9.5%) were observed. Mean disease-free survival time was 136.2 (±13.1) months, and 2-, 5- and 10-year disease-free survival was 91%, 84%, and 67%, respectively. Mean disease-free survival inversely correlated with the mean tumor diameter, number of mitotic figures and proliferation rate (Ki-67 expression).