Figure 1 Hypothetical scheme for DTC monitoring to treat dormant residual disease. Patients first have their bone marrow analyzed for DTC content. Those patients negative for DTCs (that is, a good prognosis) are monitored for symptoms and DTC content only. If patients are DTC positive at the time of surgery, after surgery or both, their DTCs would be profiled to determine their proliferative status and whether they are in dormancy (set A (DTC eradication profile) and set B (dormant DTC maintenance profile) markers) or recurrence (recurrence markers) mode. If recurrence markers are found, patients are treated with available conventional or targeted anti-proliferative treatments alone or in combination with a dormancy-inducing therapy, when available. If patients show markers of dormancy maintenance, they could be treated with potential drugs to prolong this state. DTC profiling could reveal whether specific pathways are also activated to attempt a DTC eradication strategy (using set A markers) immediately or shortly after anti-proliferative plus dormancy-inducing or dormancy-maintenance treatment schedules. MRD, minimal residual disease.

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