Figure 2
From: Oscillatory dynamics in a model of vascular tumour growth - implications for chemotherapy

Illustration of the mechanims causing oscillatory solutions. Diagram explaining how tumour cell proliferation and vessel occlusion sustain the limit cycle oscillations in system (19)-(20). The expanding tumour cell population occludes vessels, leading to reduced oxygen levels and reduced tumour cell division. The shrinking tumour cell population allows vessel recovery and the cycle repeats.