Evolution of Metastatic Disease: The Need for Monitoring and Emerging Therapeutic Opportunities

During the last few years tailored therapies have improved overall survival of patients with metastatic disease. However, iatrogenic selection pressure continues to drive the evolution of systemically spread cancer cells, resulting in the generation of aggressive and therapy-resistant tumor cells. The outcome is cancer relapse and death in the majority of patients. In early disease stages, (neo) adjuvant targeted therapies often fail for unknown reasons. Therefore, diagnostic and therapeutic strategies have to be reevaluated on the basis of an evolutionary concept of disease. This obviously implies the ability to monitor the molecular evolution of the disease. To this end, a novel diagnostic pathology for systemic cancer has to be developed that will enable precision medicine for cancer patients.