Breast cancer prevention research hub

IBIS-II-O: Observational long-term follow up study of participants from the IBIS-II DCIS and Prevention clinical trials of drugs for breast cancer prevention

The IBIS-II-O study is checking the long-term health of over 3,000 UK women who previously took part in breast cancer prevention trials. Researchers are securely reviewing NHS health records until 2031 to see how well the medicine anastrozole protects against breast cancer over many years, without requiring extra clinic visits.