Pulmonary Embolism in a Patient with Primary Renal Synovial Sarcoma: The Important Differential Diagnosis of Tumor Embolism and Its Therapeutic Implications

Pulmonary tumor embolism rarely occurs in epithelial-derived tumors, but it has been described in different tumor entities. Microscopic pulmonary tumor embolisms are often only discovered on autopsy. Pulmonary thromboembolism, on the other hand, is a frequent complication in cancer patients, and surgery in patients with a malignant tumor is an additional risk factor. The differential diagnosis between pulmonary thromboembolism and pulmonary tumor embolism can be challenging. In this case report, we describe the rare case of a patient with primary renal synovial sarcoma and the workup for a thrombus in the left pulmonary artery.