The Clinical Actionability of ctDNA and Molecular Radiotherapy
2026 marks the year that radiation therapy stopped being "blind" to the microscopic status of the patient’s cancer.
ctDNA-Guided Treatment Escalation: Circulating tumor DNA (ctDNA) is now used as a real-time marker of Minimal Residual Disease (MRD). Following a course of radiation, clinicians use ctDNA tests to determine if a patient is "molecularly cured."
Patients who are ctDNA-negative can safely be spared from toxic adjuvant chemotherapy.
Patients who remain ctDNA-positive are immediately escalated to personalized immunotherapy or targeted "boost" radiation.
Functional Personalization: Decisions are increasingly made based on the tumor's molecular profile—mutations, receptor expression, and microenvironmental signatures—rather than just the organ of origin. In 2026, radiation doses are "sculpted" based on Radiomics, identifying aggressive "habitats" within a tumor that require higher doses while sparing sensitive, responsive zones.