Both contribute. There’s definitely individual variation. Just like you have androgen receptors you have estrogen receptors, which the expression depends on genetics. That’s why some people respond very well to androgen deprivation treatments like CPA. Yet others do not always respond well to it. Same thing can be said for estrogens, however, estrogen in itself does combat androgens too. So in a sense of course estrogen is most likely to cause an improvement because it has a multi factorial effect. Whereas CPA is only addressing androgens. CPA can be detrimental for some people because reducing testosterone also reduces estrogen. It really does just depend on the person.