Fig. 2.

Comparison for a theoretical patient with neuroblastoma: the course under current care protocols (top panel) of a patient with neuroblastoma and the projected course after the routine implementation of liquid biopsy diagnostics (bottom panel). Current treatment protocols evaluate the primary tumor only at diagnosis and relapse. A subclone harboring an ALK mutation is able to remain undetected until overt clinical relapse and is able to develop resistant to therapy. The tumor burden can be monitored more continuously using liquid biopsies. The subclone harboring the ALK mutation could be detected earlier, and treatment with an ALK inhibitor initiated without first observing a clinical overt relapse. Earlier treatment could possibly prevent a resistant subclone from expanding, thus, potentially improving outcome for the patient