Figure 6
From: Oscillatory dynamics in a model of vascular tumour growth - implications for chemotherapy
Solution profiles prior to therapy. Three snapshots of the spatial domain showing how the tumour cell density varies in space at the point in time (t = 200 in dimensionless units) at which chemotherapy is applied; the results of chemotherapy in these cases are presented in Figure 7. (A) Solid line depicts the cell density at the point in time at which chemotherapy is applied (t = 200 in dimensionless units), while the dotted line shows it at approximately 145 days before start of therapy (t = 100 in dimensionless units). From the spatial spread that occurs between these time points (82.15 dimensionless spatial units, corresponding to 0.29 cm in dimensional terms) we calculate the wave speed to approximately 0.002 cm/day. Parameter values: η0 = 10.0, d p = 0.5, d s = 4.8 × 105, D s = 2.0 × 105, D v = 1, h s = 1.6 × 106, s β = 0.4, σ p = 3.7 × 104 with δ = 9 (case A), δ = 11 (case B) and δ = 11.6 (case C). Numerical solution obtained with Δx = 25/900 for the domain size L = 250 with initial conditions (p(0, 0), v(0, 0), s(0, 0), c(0, 0)) = (0.01, 1, 10/12, 0) and (p(x, 0), v(x, 0), s(x, 0), c(x, 0)) = (0, 1, 10/12, 0) for x: 0 <x ≤ 250.