NEPHRON SPARING SURGERY FOR CENTRAL RENAL TUMORS: EXPERIENCE WITH 33 CASES

Abstract

Purpose: Nephron sparing surgery is standard treatment for small, peripherally located renal cell carcinoma. In patients with a solitary kidney, bilateral tumors or impaired renal function nephron sparing surgery provides the only option to nephrectomy and subsequent hemodialysis or transplantation. We retrospectively investigated the value of nephron sparing surgery for centrally located renal cell carcinoma. Materials and Methods: Between 1969 and 1997, 311 renal tumor enucleations were performed at our institution. The tumor was centrally located in 33 cases. The indication for enucleation was elective in 7 cases and imperative in 26, including bilateral tumor in 16 (metachronous in 9 and synchronous in 7), chronic renal failure in 4 and solitary kidney in 6. Four patients had metastasis at enucleation. Results: Convalescence was unremarkable in 28 cases. Hemorrhage occurred in 1 patient, a urinary fistula in 2 and a local abscess secondary to a urinary fistula in 1. One patient died postoperatively of heart failure. Average serum creatinine was 1.25, 1.63 and 1.33 mg./dl. preoperatively, at hospital discharge and at a mean followup of 33 months, respectively. Hemodialysis was necessary transiently during convalescence in 1 patient and permanently starting 6 years after enucleation in another. Definitive histology revealed oncocytoma in 4 cases and renal cell carcinoma in 29. Disease was stages pT1 to pT3 in 9, 18 and 2 cases, and grades 1 to 3 in 6, 18 and 5, respectively. Local recurrence developed in 2 patients. Mean followup was 5.2 years (range 0.3 to 16.7). At a mean followup of 6.2 years (range 0.7 to 16.7) 20 patients were free of disease. In addition to the patient who died postoperatively, 9 died of renal cell carcinoma at a mean of 1.6 years (range 0.3 to 5.3) and 3 died of other causes at 5, 11 and 12 years postoperatively, respectively. No patient who underwent elective enucleation died. Conclusions: Nephron sparing surgery for centrally located kidney tumors is technically feasible and associated with an acceptable complication rate. Local tumor control is excellent, and the overall prognosis depends on contralateral disease and metastasis. Benign tumors may be diagnosed and removed without loss of the kidney. By avoiding hemodialysis quality of life is improved.