Percutaneous CT-Guided Cryotherapy of Renal

Masses: Long-term Follow-up and Morbidity.

Hussein D. Aoun, M.D

Wayne State University / Detroit Medical Center

Department of Radiology

Peter J. Littrup, M.D.

Professor of Radiology. Urology & Radiation Oncology:

Wayne State University/ Karmanos Cancer Institute

Why ICE?Why ICE?

• Cryotherapy = ‘Freezing’ needles accurately placed and monitored to sculpt treatment zone.

• Cryo:– Historical established: 7-yr. prostate data – it works with low

morbidity!

– Painless with minimal sedation.

– CT visible ice.

– Preservation of collagenous architecture

~ healing potential…

Cryotherapy Technology Cryotherapy Technology Transition:Transition:

Laparotomy to Percutaneous Laparotomy to Percutaneous

Percutaneous Freeze PlanningPercutaneous Freeze Planning00oo Visible MarginVisible Margin by CT/US/MRI by CT/US/MRI

~2.5 cm~2.5 cm ~4.5 cm~4.5 cm

IsothermsIsotherms, , tissue typestissue types and and heat loadheat load are important for necrosisare important for necrosis

-20-20oo ~ ~ Lethal for ‘watery’ tumors Lethal for ‘watery’ tumors

~ 4 mm inside ice ~ 4 mm inside ice -40-40oo ~ Lethal for fibrous tumors ~ Lethal for fibrous tumors

~ 8 mm inside ice~ 8 mm inside ice

-150-150oo ~ Probe surface temp ~ Probe surface temp

Renal Cryotherapy: 3/2008Renal Cryotherapy: 3/2008Methods & MaterialsMethods & Materials::

100100 masses, masses, 9090 patients patients in in 9898 procedures procedures

• 23 Saline & 4 balloons – Bowel Protection23 Saline & 4 balloons – Bowel Protection

• All outpatients – low pain during/afterAll outpatients – low pain during/after

• Complications - 3% CTCAE grade Complications - 3% CTCAE grade >> 3 3

• Mean F/U: 1.3 yrs; 47 >12mo; up to 5 yrs.Mean F/U: 1.3 yrs; 47 >12mo; up to 5 yrs.

• Recurrences – 4% - all early; probe fail/VHLRecurrences – 4% - all early; probe fail/VHL

Average Tumor Size: 3.1cm {1.2-7.6}Average Tumor Size: 3.1cm {1.2-7.6}Average Ice Ball Size: 5.5 cm {3.1-Average Ice Ball Size: 5.5 cm {3.1-

9.7}9.7}

Con-ArterialCon-Arterial

Ablation Zone Follow-up: SizeAblation Zone Follow-up: Size• CT/MR (-, +, delay) - 1, 3, 6, 12, 18, 24 monthsCT/MR (-, +, delay) - 1, 3, 6, 12, 18, 24 months

Long - Term Change of Ablation Zone Size

0

1

2

3

4

5

6

Tumor Ice Ball 1 3 6 12 18 24

Time after Cryotherapy (Months)

Av

g.

Dia

me

ter

(cm

)

Renal Cryotherapy: KCI Renal Cryotherapy: KCI Results: Local RecurrencesResults: Local Recurrences

• 6% (6/100) of 6% (6/100) of massesmasses• 7% 7% (6/90) of (6/90) of patientspatients

- 4 early experience (1st case undertreat near bowel, 1 - 4 early experience (1st case undertreat near bowel, 1 probe failure and 2 probe failure and 2 image only - Bx neg & no progress)image only - Bx neg & no progress)- 2 multi-focal tumor recur (VHL, pap Rca)- 2 multi-focal tumor recur (VHL, pap Rca)

Perc. Renal Cryotherapy Conclusions:Perc. Renal Cryotherapy Conclusions:

• Minimal Pain –Outpatient Procedure!Minimal Pain –Outpatient Procedure!

• Excellent Visualization of ICE under CT!Excellent Visualization of ICE under CT!

• Balloon / Saline protection - adjacent organs!Balloon / Saline protection - adjacent organs!

• Any location in the Kidney with good healing!Any location in the Kidney with good healing!

• CURATIVE MINIMALLY INVASIVE CURATIVE MINIMALLY INVASIVE TREATMENT OPTION FOR KIDNEY TREATMENT OPTION FOR KIDNEY TUMORS!!!TUMORS!!!