UNUSUAL CAUSE OF PROPTOSIS AN INTERESTING CASE SERIES

Haemangiopericytoma is a vascular tumor of mesenchymal origin. It is a cellular variant of SOLITARY FIBROUS TUMOUR COMPLEX. These tumors are slow growing and have overlapping morphological and immunohistochemical features. We present 5 cases who presented to our institute from Jan 2013 to Dec 2013. The mean age at diagnosis was 42.2 years. All patients had a non pulsatile swelling involving the superior orbit causing painless proptosis. All underwent superior orbitotomy with mass excision biopsy. Histopathology revealed capsulated tumor formed by spindle shaped cells with interspersed vascular channels. Immunohistochemistry was strongly positive for CD34. On follow up two out of five patients showed recurrence. Recurrent orbital SFT has the potential for malignant transformation. Considering the chance of recurrence and malignant transformation, correct diagnosis and management is essential. Metastasis develops late in the clinical course indicating long term follow up is required.