Abstract
INTRODUCTION: Bilateral renal cell carcinomas with different histological types are rare. We report herein the first description of bilateral renal carcinomas with clear cell renal cell carcinoma and mucinous tubular and spindle cell carcinoma occurring synchronously. CASE PRESENTATION: A 62-year-old man was referred to our hospital with bilateral renal tumors. The tumors on each side showed different findings from both contrast-enhanced computed tomography and magnetic resonance imaging. The tumors were partially resected. Histopathological and immunohistochemical examination of the left renal tumor diagnosed clear cell renal carcinoma. Histopathological and immunohistochemical examination of the right renal tumor diagnosed mucinous tubular and spindle cell carcinoma. CONCLUSION: We encountered a case with clear cell renal cell carcinoma and mucinous tubular and spindle cell carcinoma occurring simultaneously in bilateral kidneys.