NCT06184750 · National Cancer Institute (NCI)
Finding the Best Tamoxifen Dose for Breast Cancer Risk Reduction in Premenopausal Women, RENAISSANCE Trial
What this study is about
This phase II trial evaluates response-guided low-dose tamoxifen for reducing breast density in women who are at higher than average risk for breast cancer. Increasing breast density is a well established risk factor for breast cancer. Tamoxifen is a selective estrogen receptor modulator. It works by blocking the effects of the hormone estrogen in the breast.
View original scientific description
This phase II trial evaluates response-guided low-dose tamoxifen for reducing breast density in women who are at higher than average risk for breast cancer. Increasing breast density is a well established risk factor for breast cancer. Tamoxifen is a selective estrogen receptor modulator. It works by blocking the effects of the hormone estrogen in the breast. Tamoxifen has been shown to reduce breast density, even at reduced dosages, and is approved for the prevention of breast cancer.
Interventions
PROCEDURE
Biopsy Procedure
Undergo biopsy
PROCEDURE
Biospecimen Collection
Undergo collection of blood samples
PROCEDURE
Mammography
Undergo mammography
OTHER
Questionnaire Administration
Ancillary studies
DRUG
Tamoxifen
Given PO
Primary outcome measures
Response at any time point
Time frame: Up to 18 months
Tamoxifen response is defined as absolute dense area reduction (aDAR) of \>= 10% on mammogram compared to baseline mammogram. A one sample exact binomial test for one proportion will be used, and the exact two-sided p-value will be reported. Response rate for the entire study population, as well as for the group of women who were dose-escalated, will be estimated and reported with the corresponding 95% confidence interval. Absolute and relative changes in dense area will be estimated using descriptive statistics (e.g., mean and standard deviation, or median and interquartile range), and, as a sensitivity analysis, a paired t-test or the signed rank test will be used to determine whether there was a reduction in dense area. Similar descriptive statistics will be performed in each dose sequence group for both the response rate and dense area changes.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Premenopausal women at the time of enrollment defined by any of the following:
- Age under 50 years and regular menstruation (most recent period within the past 3 months)
- Age under 50 years and continuous hormonal contraception use and at least one intact ovary
- Women who are not postmenopausal based on serum hormone levels. Women with estradiol =\< 30 pg/mL, follicle-stimulating hormone (FSH) \>= 30 IU/mL are eligible
- Women with any of the following:
- A history of unilateral estrogen receptor (ER) positive ductal carcinoma in situ (DCIS) with local therapy completed (as determined by treating physician recommendation and patient acceptance) at least 1 month prior to study entry. (The untreated breast will be the study breast, for both imaging and optional biopsy)
- Recent or prior lobular carcinoma in situ (LCIS), or any form of epithelial atypia, flat epithelial (FEA), atypical ductal hyperplasia (ADH), or atypical lobular hyperplasia (ALH)
Where
- Tucson, Arizona
- Chicago, Illinois
- Kansas City, Kansas
- Boston, Massachusetts
- Ann Arbor, Michigan
- St Louis, Missouri
- Cleveland, Ohio
- Charleston, South Carolina
- Houston, Texas
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jun 17, 2026 · Source of record for eligibility and locations