article_snippet.sent: Tamoxifen is the main hormonal therapy drug given to women who have not been through the menopause, and is usually taken for five years or longer after treatment for breast cancer.
article_snippet.sent: Most breast cancer tumours rely on the hormone oestrogen to grow, and tamoxifen blocks oestrogen from reaching the cancer cells.
highlights_snippet.sent: Tamoxifen stops oestrogen reaching tumour cells, so Tamoxifen do not grow .
  