Multiple circular pleural metastases of renal cell carcinoma

Abstract

A 91-year-old woman was admitted with persistent pyrexia, anorexia and weight loss. A chest radiograph showed multiple circular masses of various sizes. Chest computed tomography revealed multiple pleural tumors without any lung lesion. The ultrasound-guided biopsy specimens demonstrated diffusely-proliferated tumor cells with clear or vacuolated cytoplasm, which were positive for CD10, PAX8, vimentin and CAM5.2, but were negative for mesothelial cell markers such as HBME-1 and thrombomodulin. These findings indicated metastatic clear cell carcinoma of the kidney, and a solitary renal tumor was observed on abdominal computed tomography. It has been reported that pleural metastases constituted 12% of patients with progressive renal cell carcinoma, and most of the pleural metastases occurred secondary to lung metastasis. This was a rare case of renal cell carcinoma with an unusual chest image via an intriguing metastatic pathway, which was limited to pleura.

Malignant Pleural Effusion As the Initial Presentation of Renal Cell Carcinoma: A Case Report and Literature Review

“…Pleural involvement is very uncommon. In a study conducted in Japan, pleural involvement was found in up to 12% of autopsied patients [ 18 , 19 ]. Pleural involvement in renal cell carcinoma can be explained by the flow of blood from renal veins into the bronchial and intercostal veins via Batson's plexus and through lymphatic spread [ 11 , 19 ].…”