[Recurrent malignant solitary fibrous tumor of the orbit].

A 53-year-old female patient presented with a palpable mass in the right medial orbit which had been present for 18 months. The left eye had been enucleated in childhood due to a perforating injury. An orbital biopsy performed ex domo showed unspecific inflammatory tissue but no definite diagnosis was made and systemic therapy with corticosteroids was unsuccessful. A second orbital biopsy was performed in our clinic and revealed a solitary fibrous tumor (SFT) of the orbit. Medial orbitotomy with tumor excision followed and the histological examination of the excised tumor established the diagnosis of SFT of the orbit with focal sarcomatous transformation. The patient presented 3 years later with a new orbital mass in a control MRI examination. Relapse was suspected and orbitotomy with excision of the mass was performed. The histological examination revealed a relapse of the SFT with sarcomatous transformation in the whole extent of the tumor. Radiotherapy with a dosis of 59.4 Gy was subsequently performed. The patient remained tumor-free in the most recent control examination 3 years later.