Cancer Research UK partnered with the Royal Marsden NHS Foundation Trust and Guardant Health to make ctDNA testing freely available to hundreds of advanced solid-tumor patients across the ECMC network. The initiative plans to offer at least 500 Guardant360 Liquid CDx tests, acting as a proof of concept for broader UK-wide genomic testing capacity. The partners said the program supports precision medicine trials that use ctDNA profiling and aligns with the National Cancer Plan for England. Royal Marsden previously used the Marsden360 blood test, and the new collaboration aims to increase throughput and access across participating cancer centers. Guardant360 Liquid CDx was recently approved by the FDA for ctDNA analysis, strengthening the case for translation into routine oncology decision-making as the UK expands liquid biopsy infrastructure.