TRACERx as an Optimized Paradigm for Understanding Cancer Evolution

The Tracking Cancer Evolution Through Therapy (TRACERx) program represents the most comprehensive effort to characterize tumor evolution in real time. Through longitudinal, multiregion, and multiomic profiling of tumors—and particularly of non-small-cell lung cancer and clear cell renal cell carcinoma—TRACERx has illuminated the dynamic interplay between genetic, nongenetic, and (micro)environmental factors that drive cancer progression, immune evasion, and therapeutic resistance. A central insight from TRACERx has been that not all tumor evolution is genomic: Transcriptomic diversity, epigenetic alterations, RNA editing, and changes in cell–cell interactions also drive adaptation. Methodological innovations—including tumor-informed and ultrasensitive circulating tumor DNA assays, representative sequencing, and integrative immune–genomic analyses—have yielded biomarkers resistant to sampling bias and/or predictive of recurrence, metastasis, and treatment response. By demonstrating that intratumor heterogeneity is a key determinant of clinical outcome and revealing its molecular, transcriptional, and ecosystem-level drivers, TRACERx has established a framework for linking evolutionary dynamics to patient care. As both a scientific framework and a clinical paradigm, TRACERx demonstrates how adaptive, iterative research can refine evolutionary models, improve patient risk stratification, and inspire next-generation cancer evolution studies across malignancies.