callalloo, you are right, "cause" was a poor choice in words. It probably came from my continuing explanation ("Why did I get cancer?") and justification ("Why should I take this aromatase inhibitor?") conversation in my head. Actually, the hormone imbalance language derived from Block's Life Over Cancer: "...a tumor is merely the most obvious symptom of an altered, unbalanced system...this biological imbalance creates an environment for cancer to recur: tumor cells use the body's own healthy resources to grow and multiply." (p.2-3) He argues for using every defense possible to make one's biochemical terrain hostile to cancer cells after the tumor has been removed. The reduction of estrogen is, unfortunately, a main strategy in treatment of ER+ cancer. I say unfortunately because I believe in the power of estrogen for heart, mind, bone, and general body well-being. That said, yes our contaminated environment undoubtedly triggers our cancers and an anti-cancer diet changes our biochemistry in a good way.