Systematic Review and Meta-Analysis of Preoperative Imaging Prediction of Renal Cell Carcinoma Tumour Thrombus Inferior Vena Cava Wall Invasion

AIM:To summarise published evidence assessing the preoperative diagnostic performance of identifying inferior vena cava (IVC) wall invasion in patients with renal cell carcinoma (RCC).MATERIALS AND METHODS:A systematic approach was used to identify studies that assessed IVC wall invasion with non-invasive imaging preoperatively. Search limits included English language and human study participants. A meta-analysis was conducted using random effects models to compare radiographic vascular size parameters and the association of IVC wall invasion.RESULTS:A total of 15 studies were identified, which included computed tomography (CT), magnetic resonance imaging (MRI), positron-emission tomography (PET), and ultrasound assessment. In the majority of cases, CT and MRI was utilised with high accuracy in predicting IVC wall invasion. A meta-analysis of commonly reported radiographic vascular size parameters found that IVC wall invasion was associated with greater IVC maximum anteroposterior (AP) diameter (mean difference [MD] = 6.58 mm, 95% confidence interval [CI]: 2.84-10.33, p=0.0006) and IVC maximum AP diameter at the level of the renal vein ostium (MD = 5.69 mm, 95% CI: 4.35-7.03, p<0.0001). Renal vein maximum AP dimension was not associated with IVC wall invasion (MD = 2.56 mm, 95% CI: -0.46-5.58, p=0.10).CONCLUSION:Multi-technique work-up, specifically CT and MRI and reporting of vascular radiographic parameters, of RCC patients with IVC tumour thrombus may be useful in predicting IVC wall invasion, thereby allowing appropriate surgical planning and patient education.