Solitary Fibrous Tumor Of The Deep Soft Tissues Of The Neck

Solitary fibrous tumor (SFT) is a rare mesenchymal neoplasm. Since its initial description as arising from the pleura, SFT has been reported at a wide range of anatomic sites. However, report of SFT in deep soft tissue of the neck is very rare. The authors present a case report of a rare atypical solitary fibrous tumor of the deep soft tissue of the neck. A 69- year-old woman presented with 1 year history of an enlarging, firm mass in the left posterolateral region of the neck. The tumor was characterized by a mesenchimal proliferation with areas of varying cellularity, a mild cellular atypia and hemangiopericytoma-like vessels. The tumor cells were positive for CD34, bcl-2 and CD99 and negative for EMA, cytokeratins (MNF116, CAM 5.2, AE1/AE3), S-100 protein and smooth muscle actin. The picture was coherent with atypical solitary fibrous tumor. At 2 years after surgery the patient was well with no evidence of recurrence.