To give an overview of the clinical findings. To illustrate the CT and pathological findings. To emphasize the differential diagnosis.

Pulmonary tumor emboli (PTE) are grouped into two main categories: large, proximal emboli and smaller emboli in the microvasculature. Although usually considered rare, PTE are found in up to 26% of autopsies of patients who die from cancer. Autopsy often reveals intravascular pulmonary metastases, particularly in patients with choriocarcinoma or breast, stomach, liver, kidney, lung, or prostate cancer. Tumor emboli in the pulmonary arteries may manifest with various patterns on CT, depending on the size of the vessels affected. Occasionally, pulmonary tumor embolism may be...

Clinical findings: The clinical presentation of PTE depends on the number of vessels affected; patients may be asymptomatic or, in the case of disseminated PTTM, present significant dyspnea. The main clinical sign is subacute, progressive dyspnea with hypoxemia and tachycardia, but its course may also be acute. Clinically, PTE and pulmonary thromboembolism are nearly indistinguishable, and PTE is often mistaken for thromboembolism. Pulmonary tumor microembolism is an under-recognized cause of respiratory failure in patients with cancer. The mean age of PTTM patients is 52.4 years...

The radiological diagnosis of PTE may be difficult, particularly in the case of PTTM (multiplanar and MIP reconstructions are essential); awareness of the clinical findings can help ensure timely and appropriate management as well as a more favorable prognosis. PTTM is a rare condition with very high mortality. It should be distinguished from ordinary pulmonary thromboembolism and primary PH and should be considered in the differential diagnosis in patients with acute respiratory symptoms, especially in cases with an underlying cancer but also in those without....

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Diego Preciado Email: [email protected] Radiology. Corporació Sanitaria Parc Taulí. SDI-UDIAT.CD. Sabadell; Barcelona; Spain.