From January 1987 to October 1990, 20 patients (16 M. 4 F.) affect by localized renal cell carcinoma, underwent a conservative surgical treatment. This case study includes 8 patients with bilateral (4 synchronous-4 asynchronous), and 12 patients with unilateral renal carcinoma. In the latter group only two patients had a pathological contralateral kidney. A parenchyma sparing operation was performed electively in 10 cases and was necessary in the other 10. The tumors were found to be PT1 or pT2 in all the elective cases, except one unexpected pT3a; 1pT1, 5pT2, 1pT3a and 3pT3b in the remaining group. The follow up ranges between 1 and 36 months, two deaths in bilateral tumors cases were observed. No local recurrences have been detected up to now.