[Current treatment of small renal masses]

Incidental diagnosis of renal carcinoma (RC) is increasingly common due to widespread use of radiodiagnostic techniques for other conditions. In developed countries, incidental tumor account for more than 40% of detected tumors, and 80% of solid kidney tumors less than 4 cm in size are malignant. Standard treatment for these tumors is partial nephrectomy, and their relapse rate is 1%-2% The higher increase in diagnosis of this disease has occurred in patients aged 70 to 90 years, a group where associated comorbidities are very common. In the past two decades, in parallel to development of radiographic techniques, two ablation procedures achieving tumor necrosis through cold, cryotherapy, and through heat, radiofrequency, have become established. These procedures achieve 95% short- and long-term remissions in tumors less than 4 cm in size. In addition, since these procedures may be performed percutaneously, both complications and hospital stay have decreased. As early as in 1995, Bosniak, based on observation of the growth and behavior of small RCs for longer than 8 years, advocated a watchful waiting or active surveillance attitude. This article reports cryotherapy, our radiofrequency series, and a literature review.

In the event of elderly patients, concomitant diseases advising against surgery, multiple renal tumors, a solitary kidney, or patients who reject surgery, ablation procedures may be safe and effective when performed by expert hands, achieving mid-term oncological results similar to partial nephrectomy. Active surveillance has also been shown to be safe in the mid-term in adequately informed patients. To improve indications, new diagnostic procedures that help us differentiate the potentially more aggressive tumors will be required. Larger series and longer follow-ups are neede to confirm current results.