Radiomics-Based Unsupervised Clustering Identifies Subtypes Associated With Prognosis and Immune Microenvironment in Clear Cell Renal Cell Carcinoma: A Multicenter Study.

Clear cell renal cell carcinoma (ccRCC) exhibits marked clinical heterogeneity, limiting the prognostic accuracy of traditional staging. We developed an unsupervised radiomics-based subtyping system integrating multi-omics data to decode tumor biology and improve risk stratification. Analyzing five cohorts (n = 1700, including surgical cohorts and an advanced ccRCC cohort receiving combined tyrosine kinase inhibitor and immunotherapy [T-I] treatment), we extracted 1834 CT radiomic features, applying consensus clustering to a discovery cohort (n = 748) and validating across centers. Two subtypes emerged with distinct recurrence risks: Cluster 1 and Cluster 2 (adjusted HR = 2.75 for recurrence, 95% CI 1.42-5.33, P = 0.003). Cluster 2's high recurrence risk was validated in three external cohorts (adjusted HRs: 1.76, 4.33, and 3.09; all P < 0.05). Radiogenomic analysis revealed Cluster 2 showed a higher frequency of VHL mutations and KDM5C mutations compared to Cluster 1, a more immunosuppressive microenvironment (reduced CD8+ T cell infiltration, P < 0.01; suppressed interferon signaling pathways, Gene Set Enrichment Analysis P < 0.05), and lower PD-L1 expression. In the T-I treated advanced ccRCC cohort, Cluster 2 patients had shorter overall survival. This first unsupervised radiomic system stratifies ccRCC by recurrence risk, molecular drivers, and treatment efficacy, offering a framework for precision oncology.