[Rare kidney tumors in an adult].

Rare kidney tumors can either be benign or malignant. Benign tumors include epithelial tumors and mesenchymatous ones developed from kidney cells. Malignant tumors are represented by the carcinoma of the collecting tubes as well by the sarcoma. Other malignant tumors of the extra-renal origin are also observed as lymphomas and neuro-endocrine tumors.