Dianne,
This is a very interesting study but I must caution that it is very early research. It is done on cell lines and has not been trialed in a clinical setting with actual patients. Nonetheless, it is intriguing. Evening primrose oil does have estrogenic activity and is not recommended in those with a history of hormonal cancers. I would caution its use until further research is performed. I am pasting the link to the study.
http://jnci.oxfordjournals.org/cgi/c...urcetype=HWCIT