Matched comparison of radical nephrectomy vs nephron-sparing surgery in patients with unilateral renal cell carcinoma and a normal contralateral kidney

Objective: To report the long-term follow-up of a matched comparison of rad ical nephrectomy (RN) and nephron-sparing surgery (NSS) in patients with si ngle unilateral renal cell carcinoma (RCC) and a normal contralateral kidne y. Patients and Methods: Between August 1966 and March 1999, 1492 and 189 pati ents with unilateral RCC and a normal contralateral kidney underwent RN and NSS, respectively. Patients with renal impairment, previous nephrectomy, b ilateral or multiple RCCs, metastasis, and familial cancer syndromes were e xcluded. A total 164 patients in each cohort were matched according to path ological grade, pathological T stage, size of tumor, age, sex, and year of surgery. The Kaplan-Meier method and stratified Cox proportional hazards mo del were used to estimate and compare overall, cancer-specific, local recur rence-free, and metastasis-free survival and survival free of chronic renal insufficiency. The 2 groups were evaluated for early (less than or equal t o 30 days) complications and proteinuria at last follow-up. Results: At last follow-up, 126 RN patients (77%) and 130 NSS patients (79% ) were alive with no evidence of disease. There was no significant differen ce observed between patients who had RN and those who had NSS with respect to overall survival (risk ratio, 0.96; 95% confidence interval [CI], 0.52-1 .74; P=.88) or cancer-specific survival (risk ratio, 1.33; 95% CI, 0.30-5.9 5; P=.71). At 10 years, similar rates of contralateral recurrence (0.9% for RN vs 1% for NSS) and metastasis (4.9% for RN vs 4.3% for NSS) were seen i n each group, whereas the rate of ipsilateral local recurrence for patients who underwent RN and NSS was 0.8% and 5.4%, respectively (P=.18). There wa s no significant difference in the early complications between the RN and N SS groups. However, patients who underwent RN had a significantly higher ri sk for proteinuria as defined by a protein/osmolality ratio of 0.12 or high er (55.2% vs 34.5%; P=.01). At 10 years, the cumulative incidence of chroni c renal insufficiency (creatinine >2.0 mg/dL at least 30 days after Surgery ) was 22.4% and 11.6%, respectively, for the RN and NSS groups (risk ratio, 3.7; 95% CI, 1.2-11.2; P=.01). Conclusions: This retrospective study of patients with unilateral RCC and a normal contralateral kidney suggests that NSS is as effective as RN for th e treatment of RCC on long-term Follow-up. The increased risk of chronic re nal insufficiency and proteinuria after RN supports use of NSS.