A little is good but more isn't better. Whenever a new finding is announced, scientists and clinicians are doing nothing more than making their best guess at the moment. We have to stay tuned, because with more studies we can make an even better guess. They do this all day every day. And women are capable of understanding that the answers may change with further data.
Tamoxifen is a perfect example of how medical knowledge develops.
Luckily a British doctor, Arthur Walpole, thought to test tamoxifen in women with breast cancer. It was known that many cancers were sensitive to estrogen, and he hypothesized that an antiestrogen agent might help. Indeed it did. They found that it did block estrogen in the breast and brain but amazingly seemed to act like estrogen in the bones, liver and uterus. This observation led them to develop a whole new category of drugs called selective estrogen receptor modulators.