Cryoablation (CA) causes cell destruction by rapid cycles between freeze and thaw temperature. A temperature of −19.4 °C leads to complete cell death. If ice ball formation extends beyond the tumour by >3.1 mm, a temperature of −20 °C is reached in the tumour tissue [18]. Cryotherapy could be performed through a percutaneous, open or laparoscopic approach, with the majority of cases performed with the latter [8]. The percutaneous approach is associated with decreased postoperative pain, less hospital stay and shorter convalescence time but with a higher primary failure rate in comparison with the laparoscopic CA [19, 20].

In a meta-analysis, Kunkle and Uzzo [8] compared the outcome of cryoablation (n = 600; 65 % laparoscopic route) and RFA (n = 775; 94 % percutaneous route); cryoablation was associated with a lower re-ablation rate (1.3 % vs. 8.5 %), lower local tumor progression rate (5.2 % vs. 12.9 %), and fewer metastases (1.0 % vs. 2.5 %; p = 0.06) than RFA. The meta-analysis was flawed in that it was consisted of retrospective series each with their own selection biases [21]. Furthermore, RFA was primarily performed percutaneously (compared with laparoscopic cryoablation) where incomplete treatment and re-ablation is more commonly acceptable because retreatment is easier to perform [21]. In another meta analysis by Kunkle et al. [22] analyzed 99 studies with 6471 small renal tumours (<4 cm) managed with partial nephrectomy, cryoablation, RF ablation, and observation. The local recurrence was overall more frequent after RFA (11.7 %) than CA (4.6 %). Both techniques had significantly increased local progression rates compared with surgery (relative risk 7.45 for CA and 18.23 for RFA). Progression to metastatic disease though was described in 1.2 % of cases after CA and 2.3 % of cases after RFA, with no statistical difference compared with partial nephrectomy.

HIFU uses high intensity ultrasound waves that focus on the tumor under imaging guidance and aiming to achieve a temperature sufficient for immediate thermal destruction of all tissues within the target zone. Current problems include the intervening tissues and the mobility of the kidney during breathing [23]. In a very recently published study, including 17 renal tumours HIFU achieved local tumor control in 2/3 of the lesions [24]. This technique is still considered experimental and further studies are required to define its role in the management of localized RCC [5, 24].