Approach to Renal Incidentaloma

Incidental renal masses are extremely common. As multidetector CT has come to play a more central role in medical care and as CT image quality has improved, there has been an increase in the frequency of detecting incidental renal findings. Most of these incidentalomas represent benign renal cysts, but some of incidental renal masses are not benign. Most renal cell carcinomas are discovered incidentally when an imaging examination is performed to evaluate a nonrenal complaint. Therefore, differentiating incidental benign renal masses from those that are potentially malignant is important. There are well-established, time-tested, image-based criteria that can be used to diagnose most renal masses definitively. However, some renal masses remain indeterminate even after a thorough evaluation with imaging. The workup of incidentalomas is widely varied by physician and region, and some standardization is desirable in light of the current need to limit costs and reduce risk to patients. Subjecting a patient with an incidentaloma to unnecessary testing and treatment can result in a potentially injurious and expensive cascade of tests and procedures. This article discusses the evaluation, diagnosis, and treatment options of the incidental renal masses.