A case of pulmonary tumour embolism mimicking miliary tuberculosis.

Pulmonary metastases from choriocarcinoma can very rarely give rise to a 'miliary' pattern on the chest X-ray. A 23-year-old woman with a diffuse nodular pattern on chest X-ray died due to acute respiratory failure and cor pulmonale. At autopsy, choriocarcinoma of the uterus was found. In the lungs, multiple macrovascular tumour emboli within branches of pulmonary muscular arteries in the region of segmental/subsegmental bronchi were detected. There was no evidence of pulmonary parenchymal metastases, pneumonia or tuberculosis. The 'miliary' pattern of pulmonary metastases described in cases of choriocarcinoma may be due to large vessel intra-arterial tumour emboli rather than disseminated parenchymal metastases.