Introduction: Kidney cancer accounts for approximately 2-3 % of all types of cancers. Renal tumors prevalence and especially the prevalence of small renal tumors, is on the rise. About half of the tumors currently diagnosed are smaller than 4 cm. Minimally invasive methods of radiofrequency ablation technology were recently developed for the treatment of small renal tumors and are characterized by reducing the surgical and anesthetic risk. The ablation is performed with a percutaneous approach guided by ultrasound, CT or MRI. We reviewed the results of this treatment.
Methods: A total of 75 patients with a mean age of 69.5 years (27 - 90) were treated using RF during the period 2007-2014. The average tumor diameter was 28.4 mm (11-58 mm); 40 tumors were exophytic and 30 were central. Monitoring protocol after treatment included imaging after 1, 3, 6, 12 months subsequent to treatment and later annually; median follow-up time was 21 months (1 - 97).
Results: Evidence of tumor recurrence was observed in 9 patients (11.4%); 8 were treated successfully by another RF session. Cases in which recurrence was observed were characterized by a tumor larger than 30 mm (5/9) and adjacent to renal cysts (3/9); 5 of the lesions were central (endophytic) (P=0.5). One patient died due to metastatic RCC and a metastatic disease developed in two additional patients who died of other causes.
Conclusions: It is possible to destroy most of the small renal tumors by RF ablation. When the tumor size is up to 30 mm, a 94% long-term cure may be reached. In the event of renewed growth of the tumor, the treatment can be repeated with good results. In light of short-term experience, it is recommended to limit this treatment to older patients, with a short life expectancy or when anesthetic risks prohibit surgery.