Diagnosis and treatment of primary orbital angiosarcoma - a case study and review of the literature.

Primary orbital angiosarcoma is an exceptionally rare malignancy. We report the case of a 77-year-old woman who presented with a 3-week history of left proptosis and diplopia. Visual acuity measured 20/20 in the right eye and 20/63 in the left. Computed tomography demonstrated a 26 × 10 × 25 mm extraconal medial orbital mass with mass effect on extraocular muscles and extension along the optic canal into the cavernous sinus, with associated orbital roof destruction; systemic imaging showed no metastasis. Orbital biopsy and debulking revealed a vasoformative spindle cell neoplasm with atypical endothelial cells and haemorrhagic foci, positive for CD31, CD34, and ERG, confirming primary orbital angiosarcoma. Multidisciplinary review deemed complete excision unsuitable due to intracranial extension. Paclitaxel chemotherapy was initiated but discontinued following an adverse reaction; radical radiotherapy was subsequently delivered, resulting in resolution of proptosis and improved ocular motility. This case highlights the diagnostic and therapeutic challenges of orbital angiosarcoma.