Guess it just depends on what hormones. Maybe not the thyroid in particular then. Still so many unknowns. I do know that I have thyroid issues and now breast cancer. lucky me.
Receptors for the female hormones estrogen and progesterone are another key personality feature of breast cancer.
If a tumor is estrogen-receptor positive (ER-positive), it is more likely to grow in a high-estrogen environment.
The hormones will tell the receptors to stimulate or "turn on" breast cell growth. Estrogen and progesterone can increase both normal and abnormal breast cell growth.