does estrogen cause cancer in women?
This is not causation, but facilitation after the fact. Stating that estrogen causes breast cancer is like saying fertilizer causes weeds. In a garden even weeds need some soil nutrients, and if these are completely removed, the weeds can't grow...but neither can the desired plants.
Another type of cancer cell, squamous cell, can also develop on the cervix -- but it is not linked to estrogen levels. In their study, Lacey and colleagues looked at a variety of risk factors in 560 women: 124 diagnosed with adenocarcinoma, 139 with squamous cell cancer, and 307 women who did not have cancer.