Is it safe after having breast cancer with chemo and radiation to take Natural estrogens HRT?

I wouldn’t recommend it. Although you may be in remission, there are still some dormant cancer cells in your body. A good number of breast cancers overexpress the receptor for estrogen on the cell surface. Signalling through the estrogen receptor results in cell division- something you DON’T want with cancer cells.

Although plant-based estrogens are not as potent as mammalian estrogen and analogues, they are similar enough to human estrogen that they can bind to and activate the estrogen receptor. This could potentially result in activation of cancer cells that were rendered dormant by chemo and radiation.