Ettore Squillaci MD, Abstract Co-Author: Nothing to Disclose

Carmelo Cicciò MD, Presenter: Nothing to Disclose

Francesca Nucera, Abstract Co-Author: Nothing to Disclose

Guglielmo Manenti MD, Abstract Co-Author: Nothing to Disclose

Marta Rascioni, Abstract Co-Author: Nothing to Disclose

Giovanni Simonetti MD, Abstract Co-Author: Nothing to Disclose

To determine the feasibility of dynamic contrast–enhanced perfusion CT (pCT) in the evaluation of the hemodynamic response of Renal Cells Carcinoma (RCC) to cryotherapy.

35 patients (30 male, 5 female; mean age, 62 years) with cryoablated RCC via a transperitoneal approach underwent to pCT 6-8 months after cryo-therapy. pCT was performed for 65 seconds after intravenous injection of contrast medium (80 mL, 370 mg I/mL, 4 mL/sec). Perfusion parameters (Time/Density curve; Blood flow, BF; Blood Volume, BV; Mean Transit Time, MTT; Permeability–Surface Area Product, PS) were sampled in the cryoablated tumor area and in omolateral renal cortex using deconvolution-based method. A tumor was considered to have not responsive to treatments by CT evidence of pathological contrast enhancement in cryoablated area or renal mass persistence compared with the preoperative CT control. Perfusion parameters between cryoablated area and normal renal cortex were compared by Wilcoxon sum signed ranked test.

After cryotherapy, successfully ablated tumors (n= 28) showed statistically significant decrease (p<0.01) in BV (5,39 ± 1,28 mL/100 g), BF (69,92 ± 20,12 mL/100g/min) and PS (16,66 ± 5,67 mL/100g/min) value and statistically significant increased (p<0.01)) in MTT value (25,35 ± 4,3 sec) compared with those of normal renal cortex (BV: 117,86 ± 31,87 mL/100g/min; BF: 392,39 ± 117,32 mL/100g/min; MTT: 18,02 ± 3,6 sec; PS: 81,68 ± 22,75 mL/100g/min). In two patients, assessment of perfusion parameters was not feasible for breathing artefacts. Five tumours showed poor response to treatment by the evidence of nodular contrast enhancement in the region encompassing the original lesion. Two typical enhancement patterns were obtained comparing the Time-Density curves of responsive and no responsive ablated tumors.

Perfusion CT seams to be a feasible and promising technique in monitoring the effects of cryoablation therapy in RCC.

No single and thoroughly validated imaging method in monitoring of cryoablated RCC is available. pCT changes after cryoablation therapy are crucial for post treatment management.

Squillaci, E, Cicciò, C, Nucera, F, Manenti, G, Rascioni, M, Simonetti, G, Utility of Deconvolution-based Perfusion CT in Monitoring of Cryoablated Renal Cells Carcinoma.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8004967.html