The molecular analyses enabled by isolation of CTCs and cfDNA in liquid biopsies may be applied to guide different treatment strategies at different events in the initial diagnosis and treatment of patients with cancer (Figure).
SCREENING FOR PRESENCE OF DISEASE;
PATIENT STRATIFICATION AND THERAPY SELECTION (COMPANION DIAGNOSTICS);
MONITORING TREATMENT RESPONSE AND DRUG RESISTANCE; AND
DETECTION OF MINIMAL RESIDUAL DISEASE AFTER SURGERY/RECURRENCE.