Educational ExhibitAbstract No. 360 - Troubling tumors: complicating findings during hepatic tumor embolization

Abstract

No. 361 Cryoablation under real-time CT fluoroscopic guidance in renal cell carcinoma: factors affecting local tumor control T. Yamanaka, A. Nakatsuka, J. Uraki, M. Fujimori, T. Hasegawa, K. Nakajima, Y. Sugino, H. Sakuma, K. Yamakado; Department of Radiology, Mie University School of Medicine, Tsu, Japan Purpose: To retrospectively evaluate factors affecting local tumor control in cryoablation of renal cell carcinomas (RCCs). Materials and Methods: Fifty-nine patients with single RCC who underwent percutaneous cryoablation under real-time CT fluoroscopic guidance were included in this study. Feasibility, initial therapeutic response, complications, local tumor progression, and survival were evaluated. Factors affecting local tumor control were analyzed by univariate and multivariate analyses. Results: Cryoablation was completed with a planned protocol after probes were placed in the planned sites of the tumor in all patients. Tumor enhancement disappeared after initial cryoablation in 55 patients (93.3%), but residual tumors were found in the other 4 patients. Local tumor progression developed in 3 of 55 patients (5.6%) in whom tumor enhancement disappeared after initial cryoablation during the mean follow-up of 9.2 3.9 (range, 3.2-19.2 months). The univariate analysis identified the maximum tumor diameter larger than 4cm (p1⁄40.002) and iceball margin less than 3mm (po0.001) as risk factors of local tumor control, and ice-ball margin (p1⁄40.001) still remained its significance in the multivariate analysis. Tumor enhancement of uncontrolled RCCs disappeared after the second cryoablation in 6 patients and arterial embolization in 1 patient. There was no major complication but one patient (1.7%, 1/59) who required temporary dialysis due to acute renal failure. All patients are still alive with the 1-year survival rate of 100%. Conclusion: Although cryoablation is a feasible, safe, and useful therapeutic option for the treatment of RCCs, tumor size and ice-ball margin affect local tumor control.