Renal insufficiency is not a contraindication for cryoablation of small renal masses

Small, incidental renal masses are increasingly discovered in elderly patients with comorbid disease, such as chronic renal insufficiency (CRI). Observation of these masses or nephron-sparing surgery is the standard of care for these patients if possible. Laparoscopic renal cryotherapy (LRC) has been shown to be equivalent to laparoscopic partial nephrectomy in short-term follow-up for management of these masses. We evaluated the effect of LRC in this subset of patients and compared it with the effect in a group of patients who were undergoing the same procedure and who had normal renal function.

Patients with CRI undergoing LRC for small enhancing renal masses were retrospectively evaluated for renal function changes after surgery. From February 2001 to July 2007, 123 patients underwent LRC; 77 of these had preoperative and postoperative creatinine levels (Cr) for evaluation, and 14 of these had renal insufficiency. Renal insufficiency was defined as a Cr level >1.3 mg/dL. Creatinine clearance (CrCl) was calculated by the Modification of Diet in Renal Disease equation. Complications were reviewed.

In patients with renal insufficiency, the mean preoperative Cr level was 2.39 mg/dL and postoperative Cr level was 2.24 mg/dL (P = 0.0497); the mean preoperative CrCl was 32.3 mL/min/1.73 m(2) and postoperative CrCl was 35.2 mL/min/1.73 m(2) (P = 0.034). In patients with normal function, the mean preoperative Cr level was 0.95 mg/dL and the postoperative Cr level was 0.93 mg/dL (P = 0.33); mean preoperative CrCl was 78.6 mL/min/1.73 m(2) and postoperative CrCl was 81.6 mL/min/1.73 m(2) (P = 0.19).

LRC appears to have minimal impact on renal function as measured by serum Cr levels. LRC is nephron sparing and can be performed regardless of preoperative renal function.