Figure 1: Example of dose prescription, D1 and D2 for two hypothetical biological planning target volumes (bPTV) producing uniform level of tumor control probability (TCP) as a function of number of fractions. Calculation performed using Equation. (3-4) with TCPinit=80%, α=0.3Gy-1, σα=0.069Gy-1, α/β=10.5Gy and bPTV1 with V1=21.3 ml, ρ1=0.5 cells/ml and bPTV2 with V2=2.8 ml, ρ2=1.4 cells/ml.