Primary mediastinal haemangiopericytoma--an unusual cause of massive haemoptysis in a young woman.

We report a case of primary mediastinal haemangiopericytoma in a 29-year-old female patient who presented with haemoptysis, cough and dyspnea. Computed tomography showed a 9 x 6 x 5 cm mass in the left posterior mediastinum. Bronchoscopic examination failed to obtain biopsy because of massive bleeding. The patient underwent left thoracotomy. Mediastinal mass and left lower lobe resection was performed despite the persistent bleeding. The lower lobe bronchus had been infiltrated by the tumour. Microscopic examination revealed a highly cellular tumour composed of round to fusiform cells, surrounded by thin walled endothelium lined vascular channels with a staghorn appearance. Immunohistochemical and molecular techniques rule out other soft tissue tumours which have a haemangiopericytoma-like vascular pattern. The patient is alive and free from tumour recurrence 6 months post-operatively.