Endobronchial metastasis from renal cell carcinoma: CT findings in four patients

Purpose: To describe the CT findings of an endobronchial metastasis from a renal cell carcinoma (RCC). Materials and methods: The CT findings and clinical features of a histologically proven endobronchial metastasis from a RCC in four patients (three male, one female; age range, 64–80 years; mean age, 69 years) were reviewed retrospectively. The location of the metastasis in the airway, shape, the degree of tumor enhancement, and the associated pulmonary parenchymal abnormalities were analyzed. Results: The histological subtype of the endobronchial metastases from the RCC was conventional in all cases. The tumors were located at the lobar ( n=1), both the lobar and segmental ( n=2), or the segmental ( n=1) bronchus. On the CT scan, the tumors were polypoid ( n=1), had a glove-finger appearance ( n=2), and exhibited branching in the airways and bronchial wall thickening ( n=1). The endobronchial metastasis from the RCC showed very high attenuation (84–128 HU), and strong enhancement (51.6–93.3 HU) on the contrast-enhanced CT images. The lung parenchymal lesions that had reticular opacities and ground glass opacities ( n=3). Conclusons: An endobronchial metastasis from a RCC appears as a strong-enhancing mass or bronchial wall thickening, accompanied by reticular opacities and ground glass opacities.