Chemo only as needed for Prostate Cancer is working well
A CLEVER NEW STRATEGY FOR TREATING CANCER, THANKS TO DARWIN Wired Magazine
Do not try to kill Prostate Cancer, but just keep it contained - dose only when needed
Constant dosing and the cancer evolves how to avoid the chemotherapy (carpet bombing)
war analogy - constant bombing and the enemy evolves a defense - bumkers
with infrequent dosing it does not have evolutionary pressure to learn from
classic example of the math that plotted how growing populations of snowshoe hares fuel the rise of the lynx that feed on them
They describe how tumor cells compete with healthy cells for energy resources such as the glucose that fuels them.
"Tumor cells vie against each other for resources. They turned to game theory to plot this dynamic and plugged the numbers into the Lotka-‑Volterra equations."
Prostate Cancer pilot test - 1/2 the drug dosing as needed lived 27 months instead of 16 months for constant dosing
they probably just considered the late stage/intense prostate cancer
Very simple bang-bang control equation( like a simple air conditioner control)
Start Dose when PSA>X, Stop does when PSA 
::Click on chart for details::