Figure 1, Key Figure. Surgery for the removal of a primary tumor (PT) induces both pro- and anti-metastatic processes.

A minor imbalance between these opposing processes during the immediate perioperative period can determine whether minimal residual disease (MRD) will progress toward accelerated growth, or revers toward dormancy/regression. In either case, the effect is often self-propagating, leading to a “snowball-like effect” that has the power to determine long-term cancer outcomes. Several perioperative interventions can be used during this critical, yet un-exploited, window of opportunity to shift the balance toward an anti-metastatic balance and potentially save the lives of operated cancer patients.