Papillary renal cell carcinoma (RCC) is known by the tendency to avascularity shown by angiography. More uncommon is the cystic variant of papillary RCC called cystoadenocarcinoma. The majority of papillary tumors are in stage I. The survival for papillary RCC is significantly higher than that for non-papillary RCC. CT-scan MNR, although non diagnostic, enhance the suspicion of a heterologous process in so called “complicated cysts”. US-guided percutaneous needle aspiration may be helpful to diagnose these tumours. We report 2 cases of cystodenocarcinoma and our considerations.
