Plain-English translation of NCT04703244 on ClinicalTrials.gov ↗ · Source last updated · Translation generated · How we translate trials
Read our Breast Cancer research guide →This study is collecting blood and leftover tissue from surgery in people whose breast cancer did not fully go away after chemotherapy or hormone therapy. Researchers will grow the cancer cells in the laboratory and study them to understand why this cancer is harder to treat and to develop better treatment options for future patients.
When breast cancer remains after chemotherapy or hormone therapy, it may be different from other breast cancers in ways we don't yet understand. This study exists to learn more about why some cancers resist treatment and to find new ways to identify and fight these harder-to-treat cancers.
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You will have breast cancer surgery as part of your regular treatment plan. During or after surgery, the research team will collect samples of your blood and any leftover cancer tissue. These samples will be used to grow cancer cells in the laboratory and study them to understand your cancer better and help develop new treatments for other patients in the future.
AI-generated summary from trial data · Aug 11, 2026 · Not medical advice
United States
Mayo Clinic
Enrollment target
~999 participants
Started
January 2021
Primary completion
January 2041
Age range
18 Years and older
Last updated on clinicaltrials.gov in March 2026.
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Central contact
Clinical Trials Referral Office
Mayo Clinic
Tell us you're interested and we'll help connect you with the research team. We'll walk you through what to expect first — no email needed to get started.