Radiomic and gEnomic approaches for the enhanced DIagnosis of REnal Cancer (REDIRECt): A translational pilot study

Introduction: The aim of this pilot study is to establish a radiogenomic characterisation of a clear-cell renal cell carcinoma (ccRCC) subpopulation, focusing on the transcriptomic underpinnings of radiomic features. Materials & Methods: To establish the viability of conducting a combined analysis of both radiomic and genomic data, a pilot cohort of 6 patients with <5cm G2 unilateral non-metastatic T1a-b ccRCC, who underwent surgery, was evaluated. Transcriptomic analysis was conducted through RNA-seq on tumor samples, while radiomic data was extracted from pre-operative 4 phase contrast-enhanced multidetector CT scans. Genomic heterogeneity was assessed with principal component analysis run on unrestricted data, on a clear-cell renal cell carcinoma associated gene list with zero-centered Reads Per Kilobase of transcript, per million mapped reads values. The underlying pathways and gene ontologies were established with enrichment analysis. In addition, Pearson’s correlation between radiomic data and the transcription of significant genes was fitted, and dendrogram and heatmap plots were drawn. Results: Even in a clinically homogeneous population, the employed analyses have demonstrated that RCC should be regarded as an intrinsically heterogeneous disease. The analysis of the radiomic features and gene expression correlation using heatmap and dendrogram showed four distinct radiogenomic correlation patterns: with one including 5 radiomic features, and the other three including 2 features each. Conclusion: The current pilot study is the first investigation demonstrating an innovative radiogenomic characterisation of clear-cell RCC. Based on such observations, further investigation into the radiomic and genomic approaches for the enhanced diagnosis of RCC is warranted. 6 ccRCC tumor samples collected from patients who underwent surgery for RCC were collected and analysed.