[Small renal mass. Diagnostic management]

The detection of renal masses < 3 cm has continually increased over the last few years due to the improvements and wide use of imaging techniques that have made early diagnosis of renal carcinoma possible and therefore to directly influence patient survival. The approach to small renal lesions based on our experience and the data published in the literature are analyzed.

The small renal lesion is problematic and indeterminate because of its size, which makes it difficult to measure its density before and after contrast administration on CT assessment, and is the main diagnostic factor in this disease. Small renal masses constitute a diagnostic challenge whose resolution may lead to disproportionate surgery. This has led us to utilize multiphasic helical CT with specific protocols and to look for data in the natural history of the renal tumor to complement the radiological findings. Series have been published that demonstrate that the slow growth and degree of malignancy of small renal tumors warrant a regular helical CT control evaluation because it allows comparison of the findings and detects growths > 1 cm, which is a sign of malignancy and consequently an indication for surgery.

Due to the natural course of small renal tumors and the reproducibility of multiphasic CT, the correct approach is to perform close follow-up of patients at surgical risk or with an equivocal diagnosis using this imaging technique.