Multimodality staging of renal cell carcinoma—pearls & pitfalls
摘要
Accurate staging of renal cell carcinoma (RCC) is critical because small differences in imaging interpretation can alter operative planning, systemic treatment decisions, and prognosis. This educational review highlights the practical role of multimodality imaging in RCC staging, with emphasis on common interpretive pitfalls and reporting strategies that improve clinical decision-making. Contrast-enhanced CT and MRI remain the foundation of local staging, enabling assessment of tumour size, renal sinus and perinephric extension, venous tumour thrombus, and spread beyond the perinephric fascia. However, several features are prone to overcall or undercall, particularly renal sinus invasion, perinephric invasion, inferior vena cava wall involvement, and adjacent organ invasion, with direct implications for management. Regional and distant staging are likewise imperfect. Nodal assessment remains limited by the overlap between reactive enlargement and metastatic disease, while indeterminate pulmonary nodules, marrow-based bone metastases, and atypical metastatic sites may all complicate interpretation. Selected technical considerations, including the potential value of arterial phase imaging in suspected clear cell RCC and the problem-solving role of MRI in equivocal local staging, may help reduce understaging. The role of PET and emerging targeted tracers remains selective rather than routine. Throughout, emphasis is placed on management-relevant imaging findings, modality-specific strengths and weaknesses, and practical pearls derived from experience. A structured reporting approach is also proposed to improve completeness, consistency, and communication with the multidisciplinary team.