Kemal Tuncali MD, Presenter: Nothing to Disclose

Shu-Huei Shen MD, Abstract Co-Author: Nothing to Disclose

Usha Govindarajulu PhD, Abstract Co-Author: Nothing to Disclose

Paul Richard Morrison MSC, Abstract Co-Author: Nothing to Disclose

Servet Tatli MD, Abstract Co-Author: Nothing to Disclose

Stuart George Silverman MD, Abstract Co-Author: Consultant, Galil Medical Ltd, Yokneam, Israel Consultant, Siemens AG

Paul B. Shyn MD, Abstract Co-Author: Nothing to Disclose

00030490-DMT et al, Abstract Co-Author: Nothing to Disclose

To evaluate changes in renal function following renal tumor cryoablation and identify risk factors for renal function deterioration.

Baseline, postprocedural nadir (within 7 days), and ultimate (after 7 days) estimated glomerular filtration rates (eGFR) of 45 consecutive patients treated with CT-guided percutaneous cryoablation for a single renal tumor were retrospectively recorded. We considered risk factors of age (mean: 68.4), gender (28 male; 17 female), solitary kidney (n=7), baseline eGFR (median: 74 ml/min/1.73m2; range 17-107), baseline chronic kidney disease (CKD) stage (median:2; range 1-4), tumor location (16 upper pole; 14 lower pole; 15 interpolar), tumor diameter (mean: 2.2 cm; range 0.9-4.4), and ablated normal renal parenchyma volume calculated using 24 hr postprocedure MR images and manual segmentation (mean: 20.3 cm3; range 3.3-61.3). The eGFR at nadir and at ultimate were each analyzed in a multivariate regression model adjusted by baseline, change in CKD, solitary kidney, and age. There was no evidence of postprocedural hematoma, urinoma, obstructive uropathy, or other structural kidney injury.

The medians of the percent changes from baseline to postprocedural nadir eGFR and to ultimate eGFR were –9% and –4% respectively. In the postprocedural 7 day period, worsening in CKD stage occurred in 6 patients (13%); all had eGFR change from baseline of ≤ –20%. After the first 7 days postprocedure, worsening in CKD stage persisted only in 3 patients (7%). Multivariate regression model suggested that only baseline eGFR (p<0.0001) and change in CKD (p<0.0001) were predictive of nadir and ultimate eGFR, while none of the other parameters was predictive, except age (p<0.08) for ultimate eGFR.

Percutaneous CT-guided cryoablation of renal tumors may rarely cause renal function deterioration, is usually transient, and is more likely to occur in patients with baseline impaired renal function or advanced age.

It may be prudent to minimize the ablation margin during percutaneous cryoablation of renal tumors in elderly and patients with renal insufficiency, using the CT-visible iceball as a guide.

Tuncali, K, Shen, S, Govindarajulu, U, Morrison, P, Tatli, S, Silverman, S, Shyn, P, et al, 0, Impact of Percutaneous CT-guided Cryoablation on Renal Function: Analysis of Risk Factors.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8014869.html