Effect of combination of systemic therapy and local therapy with cryoablation on outcome in metastatic renal cell cancer (mRCC): An extended follow-up report

e15081 Background: Resection of metastasis in renal cancer (mRCC) yields 5-year survival rates of 20% to 30%. Yet most patients (pts) poor surgical candidates or have unresectable disease. Percutaneous cryoablation is a minimally invasive procedure employed for local therapy of metastatic foci, but its role in inducing long term remissions in combination with systemic therapy is unknown. Methods: Following IRB approval and HIPAA compliance, a retrospective review of records for pts receiving cryotherapy and systemic targeted therapy from 2004-2007 at Karmanos Cancer Institute was performed to enable a minimum follow up of 3 years. OS was estimated using the Kaplan-Meier methodology. Results: Of the 27 patients identified 85% were male, 88% Caucasian, and 77% had clear cell histology. 2 pts had sarcomatoid mRCC. All patients had prior nephrectomy. 24 patients had multiple metastatic sites: 9 with 2 sites, 8 with 3 sites and 7 with ≥ 4 sites. 15%, 52%, 11%, and 22% had favorable, intermediate, poor, and indeterminate MSKCC risk score, respectively. Systemic therapy was interrupted for at least 1 week prior to and after cryotherapy and resumed after complete healing. One major complication of nerve paresis was noted from lumbar paravertebral mass cryotherapy. Median number of ablations was 2 (range 1-4). Of the 60 total ablations 13%, 28%, 27%, 17%, and 15% were renal bed, visceral, soft tissue, bone, and lymph nodes respectively. The median OS from diagnosis of metastatic disease was 49.6 months (95% confidence interval: 21.2- 54.9 months).The 2 yr OS rate is 90% (95% CI: 78-100%) and 5 yr OS rate is 68% (49-87%). 8 patients (30%) are alive to date. Conclusions: The strategy of combining systemic therapy and local control of metastasis with cryoablation had favorable impact on OS in mRCC even after longer follow up. Cryoabalation is a minimally invasive, well tolerated technique, applicable to the majority of mRCC patients. Prospective investigation or case-control studies to evaluate the incorporation of cryoabalation with targeted systemic therapy in advanced RCC is warranted.