A 67-year-old man presented with dyspnoea and non-specific chest pain. A CT scan showed a mass lesion within the right superior pulmonary vein protruding into the left atrium (fig 1A, B). Positron emission tomography with ¹⁸fluoro-2-deoxy-D-glucose showed uptake within the lesion but no extrathoracic disease (fig 1C). A clinical-radiological diagnosis of pulmonary venous angiosarcoma was made and surgical resection was offered for symptom palliation. At surgery the tumour mass was found to be growing from the right superior pulmonary …