CT and MR imaging for local tumor characterization and whole-body staging in renal cell carcinoma

Background: Renal masses should undergo dedicated imaging workup for differential diagnosis and staging.Objectives: The aim of the work is to give an evidence-based practical recommendation for the imaging workup of renal masses as well as the staging and restaging in renal cell carcinoma (RCC).Materials and methods: We performed a literature search in PubMed and included the current German S3 guideline for RCC.Results: Solid or complex cystic renal masses should be characterized using multiphasic, contrast-enhanced imaging (contrast-enhanced ultrasound, computed tomography [CT], magnetic resonance imaging [MRI]). Image-guided biopsy may be performed in view of the individual clinical constellation and therapeutic consequence. If there is suspicion of RCC and for follow-up staging, contrast-enhanced CT of the chest, abdomen, and pelvis including an arterial phase of the upper abdomen is the imaging modality of choice. If there is suspicion of brain or bone metastases, MRI should be performed. Furthermore, MRI is a valid alternative to abdomen CT in younger patients or known allergy to iodinated contrast agents.Conclusion: For differential diagnosis of renal masses, multiphasic contrast-enhanced imaging is essential. For whole-body staging in renal cell carcinoma, CT is the imaging modality of choice. As an alternative and for specific constellations, MRI is a valid alternative.