Fig. 3.

(A) Fit to patient PSA values as reported in literature (29) (compare to figure 2b in reference) in response to rapid cycling intermittent androgen ablation therapy. (B) Numerical predictions of cancer response to therapy, in terms of normalized cell number. Following experimental protocol, therapy is provided for three weeks and stopped for one week, during which period testosterone is provided. The treatment schedule is continued for as long as PSA concentration decreases or remains stable (approximately 27 months from the start of therapy). At this point, patient is placed on continuous androgen ablation. Androgen-dependent cancer cells (N, black curve), and castration-resistant cancer cells (M, red curve) are plotted versus time. (C) Plot of the difference in predicted disease-free survival periods in patients on rapid cycling as described above and continuous therapy versus increasing levels of competitive advantage of N over M, represented by the nondimensional constant θ.