How (not) to misdiagnose focal renal lesions: lessons learned?

More than half of patients over the age of 50 years old may have at least one incidental renal lesion detected on imaging studies, such as ultrasonography, computed tomography or magnetic resonance imaging. Although the majority can be easily detected and correctly characterized, misdiagnoses may occur and are often related to methods limitations, inadequate imaging protocols and misinterpretation. This pictorial essay addresses recommendations on how to recognize benign and malignant renal processes that can be potentially missed or mischaracterized on imaging studies.