Purpose: We assessed safety, efficacy, and oncologic outcomes of the new innovative Liquid Nitrogen device in patients with early-stage (T1a) SRMs.
Materials and Methods: 74 patients (mean age: 69y; 68% males) with 78 lesions (mean: 2.35 cm) smaller than 4 cm, were included; Mean R.E.N.A.L score was 6.53; 16% were endophytic. Percutaneous cryoablation using ProSense™ (10G/13G; IceCure Medical Ltd, Caesarea, Israel) was performed in all patients under CT guidance with sedation/light general anesthesia. It`s extremely low temperatures (-1960C) produces larger lethal zone per needle. All procedures were done in two cycles of freezing with intervening passive thaw. Patients underwent imaging and clinical surveillance every 3 months during first year and annually thereafter. Oncologic success was indicated by a reduction in lesion size and lack of enhancement on follow-up CT or MRI. Safety was determined by monitoring Creatinine (Cr) and Hemoglobin (Hb) levels.
Results: Ablation was oncologically successful in all 78 lesions. Average freezing cycles was 22 minutes. Average procedure time was 50.5 min. 45 lesions were followed in 42 patients for more than 12 months (mean: 18.2 m). 3 treatment failures occurred (6.6%): of them, one is a candidate for repeat procedure. One serious event was noted; a late-onset ipsilateral hydronephrosis in a patient treated for a complex medial lower pole lesion (1.2%). Mean Cr and Hb levels remained unchanged in all patients.
Conclusion: Cryoablation of SRMs with an innovative Liquid Nitrogen cryogenic device is feasible and safe procedure, with similar oncologic results as nephron spearing surgery and with low rate of serious adverse events.
