[Neoplasm invasion of the renal vein by transitional cell carcinoma of the kidney pelvis].

We present two cases of renal pelvis transitional cell carcinoma with invasion of the renal vein. We emphasize the importance of preoperative diagnosis and review the diagnostic methods available for revealing this uncommon eventuality. Owing to the prognostic importance and subsequent surgical treatment, this possibility should be evaluated in those cases of renal pelvis transitional cell carcinoma with extensive parenchymatous invasion or in those cases in which kidney function cancellation occurs in the excretory urograph.