Border line cases and diagnostic doubts in definition kidney parenchymal and collecting tract neoplasia.

Aim of this work is to present cases of renal neoplasms where all available diagnostic modalities and control exams were applied, still explorative surgery was needed. Asymptomatic tissue mass with diagnostic findings of hypovascular renal cell carcinoma and renal pelvic carcinoma were inconclusive. While percutaneous CT guided biopsy is advisable in such cases, it was not performed due to central, hilar localization of the lesions and its small dimensions. In rare cases, such ours are diagnosis is achieved by surgery-histology examination.