NCT05501704 · Jose Pablo Leone
ETHAN - ET for Male BC
What this study is about
This research study is looking to see how well male breast cancer responds to preoperative treatment with endocrine therapy and which endocrine therapy regimen is the most effective treatment for male breast cancer.
View original scientific description
This research study is looking to see how well male breast cancer responds to preoperative treatment with endocrine therapy and which endocrine therapy regimen is the most effective treatment for male breast cancer.
Interventions
DRUG
Tamoxifen
Taken orally
DRUG
Anastrozole
Taken orally
DRUG
Degarelix
Subcutaneous (under the skin) injection
DRUG
Abemaciclib
Taken orally
Primary outcome measures
Change in Ki-67
Time frame: At the end of the 3-week window period.
Ki-67 will be evaluated by ImmunoHistoChemistry (IHC) following consensus recommendations using imaging analysis methods.
RCB index
Time frame: At time of surgery.
RCB will be determined using data from each participating institution pathology department, and will be reviewed by the study team pathologist.
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
- Men aged 18 years or older, with diagnosis of invasive breast cancer who have not undergone surgical resection of the primary tumor and axillary nodes.
- Stage I, II, or III per American Joint Committee on Cancer (AJCC) staging 8th edition (112).
- Breast cancer must be hormone receptor-positive and HER2-negative according to definition below assessed by local pathology.
- Hormone receptor-positive is defined as: positivity for at least one of the hormone receptors (estrogen receptor \[ER\] or progesterone receptor \[PR\]) by IHC. ER and PR assays are considered positive if there are \> 1% positive tumor nuclei in the samples.
- HER2-negative is defined per the current American Society of Clinical Oncology/College of American Pathologists Clinical Practice Guideline (113).
- Patients with multifocal or multicentric disease are eligible if the treating investigator has determined the patient should be treated as ER-positive and HER2-negative.
- Bilateral brea
Where
- Washington D.C., District of Columbia
- Boston, Massachusetts
- Rochester, Minnesota
- Chapel Hill, North Carolina
- Philadelphia, Pennsylvania
- Pittsburgh, Pennsylvania
- Nashville, Tennessee
- Houston, Texas
Collaborators
Eli Lilly and Company, Translational Breast Cancer Research Consortium (TBCRC)
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 Apr 30, 2026 · Source of record for eligibility and locations