Synchronous nephron-sparing approaches for bilateral renal masses: peri-operative and renal functional outcomes

Objectives: To evaluate the peri-operative and renal functional outcomes of patients undergoing synchronous bilateral partial nephrectomy (PN) or percutaneous cryoablation (PCA). Patients and Methods: We retrospectively reviewed our institutional nephrectomy and renal mass ablation registries to identify all patients with synchronous bilateral renal masses who underwent simultaneous bilateral PN (n = 76) or PCA (n = 13) between 1974 and 2013. Changes in estimated glomerular filtration rate (eGFR) as well as peri-operative complications are descriptively reported for each procedure. Results: The number of treated renal masses in the 76 patients in the PN group and the 13 patients in the PCA group was 249 and 28, respectively. The median (interquartile range [IQR]) age at treatment was 62 (50, 71) years for the PN group and 67 (56, 72) for the PCA group. The median (IQR) maximum tumour sizes were 4.6 (3.4, 6.5) cm and 2.6 (2.4, 3.2) cm for the PN and PCA groups, respectively. The median (IQR) length of hospital stay was 7 (5, 8) days for the PN group and 1 (1, 10) days for the PCA group. The median (IQR) change in eGFR from baseline to discharge was −32 (−46, −15)% for the PN group and −17% (−33, −3) for the PCA group. By 3 months, median (IQR) renal function improved, with changes of −9 (−19, 0)% and −8 (−11, 15)%, respectively, compared with baseline. No patient in either group required renal replacement therapy in the peri-operative period. Early postoperative complications (within 30 days) occurred in 16 patients (21.6%) in the PN and four patients in the PCA group. In particular, angioembolization for bleeding was required in the postoperative period in two patients (2.7%) in the PN and one patient in the PCA group. Conclusions: Our experience suggests that synchronous bilateral PN or PCA are feasible treatment options for select patients presenting with bilateral renal masses. In select cases, both approaches appear to have reasonable rates of peri-operative complications and effects on renal function.