Unusual Development of Pulmonary Tumor Embolism from Controlled Liver Metastases of Transitional Cell Carcinoma: An Autopsy Case

: Clinicians generally suspect pulmonary tumor embolism (PTE) with uncontrolled carcinomas which often spread to lungs. We, however, experienced an autopsy case of diffuse microscopic PTE despite controlled liver metastases of transitional cell carcinoma (TCC). A 66-year-old man with progressing respiratory symptoms showed almost normal chest findings on computed tomography. Although liver metastases were successfully shrunk by chemotherapy, the patient died from aggressive respiratory failure. An autopsy revealed small pulmonary vessels showing diffuse tumor emboli. TCC can cause PTE even if liver metastases are controlled. We must therefore be aware that PTE can manifest as respiratory symptoms without any computed tomography findings.