The Silent Giant: Asymptomatic Renal Cell Carcinoma With a Level III Inferior Vena Cava Thrombus.

Renal cell carcinoma (RCC) with inferior vena cava (IVC) tumor thrombus represents a complex clinical entity associated with increased surgical complexity and significant prognostic implications. We report the case of a 49-year-old asymptomatic male patient who was incidentally diagnosed with a massive right renal tumor with a Level III IVC tumor thrombus on imaging. The patient underwent successful right radical nephrectomy with IVC thrombectomy without the need for cardiopulmonary bypass. Histopathological examination confirmed clear cell RCC, Fuhrman grade II, with malignant thrombus and negative surgical margins. The final pathological stage was pT3bNxM0, corresponding to Stage III disease. This case highlights the importance of accurate preoperative imaging, multidisciplinary surgical planning, and meticulous vascular control in achieving successful thrombectomy of a Level III IVC tumor thrombus without cardiopulmonary bypass.