NCT04297020 · Jonsson Comprehensive Cancer Center
Brain Health in Breast Cancer Survivors
What this study is about
Endocrine therapy (ET) is widely used to treat hormone receptor positive breast cancer and prevent recurrence by downregulating estrogen function. However, ETs readily cross the blood brain barrier and interfere with the action of estrogen in the brain. Estrogen supports cognition and menopausal status is closely linked to cognitive health in women.
View original scientific description
Endocrine therapy (ET) is widely used to treat hormone receptor positive breast cancer and prevent recurrence by downregulating estrogen function. However, ETs readily cross the blood brain barrier and interfere with the action of estrogen in the brain. Estrogen supports cognition and menopausal status is closely linked to cognitive health in women. This has raised concern that anti-estrogen ETs may affect cognition and brain health in breast cancer survivors. However, evidence across existing studies is inconsistent and these effects remain poorly understood. The incomplete understanding of the effects of ET are likely due to limitations of earlier studies - namely, the under-appreciation of the role of menopausal status and insensitivity of standard cognitive measures. This research project will address these earlier limitations by specifically comparing ET effects by menopausal status, and using highly sensitive, task-related functional magnetic resonance imaging (fMRI) measures to assess the effects of ET on brain function.
Primary outcome measures
Brain activity comparison between breast cancer survivors undergoing endocrine therapy and healthy matched control subject.
Time frame: Day 1
To compare brain activity using fMRI during a working memory task between breast cancer survivors on ET and matched healthy controls, and examine the interaction of menopausal status.
Cognitive function comparison between breast cancer survivors undergoing endocrine therapy and healthy matched control subject.
Time frame: Day 1
To compare cognitive function between breast cancer survivors on ET and matched healthy controls, and examine the interaction of menopausal status.
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
- Fluent in English
- Adequate vision/hearing to complete testing
Exclusion criteria
- History of major or mild neurocognitive disorder or dementia
- Diagnosis of major neurological condition (e.g., epilepsy, Parkinson's Disease, stroke)
- Diagnosis of a major psychiatric disorder (e.g., bipolar disorder, schizophrenia)
- Untreated/unstable unipolar depression or anxiety
- Prior history of cancer or chemotherapy (for controls, any history)
- History of a learning disorder
- History of head injury with loss of consciousness \>20 minutes
- History of salpingo-oophorectomy or hysterectomy
- A cardiac pacemaker
- Implanted electronic device
- Claustrophobia
- Currently pregnant
- Orbital metal implant or other metallic foreign bodies Additional exclusion criteria for controls: current use of a contraceptive agent that interferes with endogenous hormonal fluctuation (e.g., oral contraceptive pill) or precludes determination of menstrual pattern (e.g., hormonally secreting intrauterine device), or current treatment with systemic estrogen replacement therapy.
Where
- Los Angeles, California
Collaborators
National Cancer Institute (NCI)
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 Jul 7, 2026 · Source of record for eligibility and locations