[Microscopic tumor embolisms in metastasized breast carcinoma]

In two patients, women of 54 and 46 years old, with metastatic carcinoma of the breast, multiple microscopic tumour emboli in the lungs were found at autopsy. Ante mortem, unexplained respiratory distress in the former and an atypical thrombotic thrombocytopenic purpura-like syndrome in the latter were the most characteristic clinical features. Pulmonary microscopic tumour embolism is a rare diagnosis but it may occur in all types of cancer. Clinically, thrombotic pulmonary emboli are difficult to distinguish from microscopic tumour embolism. Special attention is to be paid to typical findings on radionuclide perfusion lung scanning (multiple subsegmental perfusion defects at the periphery of the bronchopulmonary segments with a normal ventilation named "segmental contour pattern'). Microangiopathic haemolytic anaemia and consumption coagulopathy are associated disorders. Tumour-directed therapy is the treatment of choice.