Nephron sparing surgery for renal tumors: indications, techniques and outcomes.

PURPOSE: A contemporary review of the indications, techniques and outcomes is presented for nephron sparing approaches to solid renal masses, emphasizing their role for the treatment of renal cell carcinoma. We also reviewed the evolving role of minimally invasive forms of parenchymal sparing renal surgery.
MATERIALS AND METHODS: MEDLINE and CANCERLIT computerized literature searches, and manual bibliographic reviews were performed to identify published peer reviewed articles pertaining to nephron sparing surgery or partial nephrectomy from 1980 to 2000. Pertinent articles were collated and reviewed.
RESULTS: Nephron sparing surgery is increasingly being used to treat patients with solid renal lesions. The technical success rate of nephron sparing surgery is excellent, and operative morbidity and mortality are low. For renal cell carcinoma long-term cancer-free survival is comparable to that after radical nephrectomy, particularly for low stage disease. The overall incidence of local recurrence is low at 0% to 10%. For tumors 4 cm. or less local recurrence rates are even less at 0% to 3%. The risk of local recurrence depends primarily on the initial local pathological tumor stage. The reported incidence of multifocal renal cell carcinoma is approximately 15% and it also depends on tumor size, histology and stage. The risk of multifocal disease is low at less than 5% when the maximal diameter of the primary tumor is 4 cm. or less. Recent advances in renal imaging limit the radiographic evaluation necessary when planning complex nephron sparing approaches. Three-dimensional, volume rendered computerized tomography integrates all of the necessary information previously obtained by conventional computerized tomography, angiography, venography and pyelography into a single preoperative test, allowing better operative planning with maximal preservation of unaffected parenchyma in the remnant kidney. Minimally invasive modalities of tumor resection or destruction should be reserved for highly select patients and await improvements in technology, standardization of technique and long-term outcomes data before they may be completely integrated options.
CONCLUSIONS: Nephron sparing surgery provides effective therapy for patients in whom preservation of renal function is a relevant clinical consideration. The importance of meticulous operative technique for achieving acceptable oncological and functional outcomes is emphasized. Accumulating data in appropriately select patients suggest a long-term functional advantage gained by the maximal preservation of unaffected renal parenchyma without sacrificing cancer control.