Residual disease monitoring converts diagnosis into recurring surveillance
Circulating tumour DNA assays detecting residual disease after surgery identify recurrence months before imaging does, and clinical practice has moved toward serial testing every three months through the highest-risk period. A patient generates four assays a year for two or three years rather than one at diagnosis. Coverage arrived alongside evidence in colorectal, breast and lung disease, which is unusual and decisive. The recurring billing pattern is why laboratory revenue has grown considerably faster than the number of patients being tested. Tumour-informed approaches requiring a tissue baseline also create switching cost that no diagnostic test has ever generated.
Market Impact: Over 90 biomarker-directed approval








