Abstract
BACKGROUND: Ablation is a method of destroying a pathological focus using a controlled temperature or other effect. The most promising ablative treatment for localized kidney cancer today is cryoablation.
AIM: To analyze functional and oncological results of cryoablation of localized kidney cancer using liquid nitrogen as cryogen.
MATERIALS AND METHODS: Between 2017 and 2020, 56 patients with suspected localized kidney cancer were observed and treated at the N.N. Petrov National Medical Research Center of Oncology. With morphological verification, renal cell carcinoma was detected in 19 (65.5%) patients, chromophobe renal cell carcinoma in 3 (10.4%), oncocytoma in 3 (10.4%), in 4 (13.8%) cases the tumor was not detected in morphological material. All patients underwent cryoablation using the MKS cryotherapy unit with liquid nitrogen as a cryogen (ultrasound-guide cryotherapy was performed in 4 (7.1%) cases, CT-guide in 46 (82.1%), laparoscopically in 6 (10.7%) patients).
RESULTS: Renal function in this study was assessed by creatinine level and glomerular filtration rate (GFR) before and after cryoablation. The creatinine level before cryoablation was 101 18 mol/l, after 113.8 18 mol/l (p = 0.21), GFR before cryoablation 63 13 ml/min, after 65 13 ml/min. These differences were not significant (p = 0.87). Local disease control was achieved in 100% of cases. The overall and specific survival rate were 100% (one patient died from synchronous primary multiple cancer at 4 years of observation), the survival rate to recurrence was 90.9 3.9%, and the event-free survival was 70.2 6.6%. During the follow-up period, 9 (16%) recurrences of the disease were diagnosed.
CONCLUSIONS: Cryoablation makes it possible to maintain a large volume of renal parenchyma, thereby not reducing the functional ability of the kidney. In addition, the outcomes and survival rates are quite high, making it an alternative option for other nephron-saving operations.