Figure 6: Evolutionary absorbing regions under therapy.

Bounded, absorbing regions are shown for treatment pairs: Lupron, Lupron & Abiraterone (A); No treatment, Lupron (B); No treatment, Lupron & Abiraterone, (C) and all treatments (D). The outer rim of the absorbing region represents the largest cycle for the pair of treatments (arrows show trajectory directionality). Any regimen will eventually be absorbed into the bounded region (3 sample sequential regimens shown). By cleverly defining treatment schedules (D), the bounded region can be expanded to find cycles in a wider region of the state space. Example shown for Lupron (blue line) to no treatment (purple line) to Lupron & Abiraterone (red line). Parameter robustness (inset shown in A, B, C): absorbing state space is shown for 36 random parameterizations subject to inequalities discussed in table S1 and S2, overlaid in transparent color (see Methods). For these given inequalities, the absorbing regions remain relatively robust to parameter changes.