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Serial FES PET/CT to Measure Hormone Expression in Patients Undergoing Endocrine Targeted Therapy

Serial [F-18] Fluoroestradiol (FES) PET Imaging to Evaluate Endocrine-targeted Therapy

Status
Active, not recruiting
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04692103
Enrollment
2
Registered
2020-12-31
Start date
2021-07-10
Completion date
2041-04-30
Last updated
2026-01-22

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Estrogen Receptor Positive, Primary or Recurrent Breast Carcinoma, Stage IV Breast Cancer AJCC v6 and v7

Brief summary

This clinical trial studies use of F-18 16 alpha-fluoroestradiol (\[F-18\] FES) positron emission tomography (PET)/computed tomography (CT) in measuring tumor hormone receptor expression in patients undergoing endocrine-targeted therapy for newly diagnosed breast cancer or breast cancer that has come back or spread to other places in the body. Comparing results of diagnostic procedures done before, during, and after hormone therapy may help measure a patient's response to treatment.

Detailed description

OUTLINE: Patients undergo F-18 FES PET/CT scan at baseline. Patients also undergo F-18 FES PET/CT and FDG PET/CT between 1-12 weeks after starting therapy, and then 1-12 weeks after the second FES PET/CT scan. Repeat FDG PET may be omitted in patients on selective estrogen receptor degrader. After completion of study, patients are followed up for up to 20 years.

Interventions

Undergo F-18 FES PET/CT

PROCEDUREPositron Emission Tomography

Undergo F-18 FES PET/CT

PROCEDUREComputed Tomography

Undergo F-18 FES PET/CT

DRUGFludeoxyglucose F-18

Undergo FDG PET/CT

OTHERLaboratory Biomarker Analysis

Correlative studies

Sponsors

University of Washington
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
DIAGNOSTIC
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Adult, non-pregnant patients with biopsy-proven or clinically obvious primary, recurrent or metastatic breast cancer * Breast cancer from ER+ primary that is seen on other imaging tests. Tumor ER expression must have been confirmed by immunohistocytochemistry of primary tumor or recurrent disease. * At least one site of disease 1.5 cm or greater is needed to meet the spatial resolution limits of PET imaging. * Patients must have been off tamoxifen or other estrogen receptor blocking agents for at least 6 weeks and off chemotherapy for 3 weeks for the initial baseline FES. * Patients must be selected for an endocrine targeted therapy regimen for treatment of their breast cancer by the referring oncologist. Selected treatments may be part of experimental treatment protocols for which the patient would be separately consented. * Patients must be willing to undergo serial imaging procedures. * Patients must agree to allow access to clinical records regarding response to treatment and long term follow up. * Ability to understand and the willingness to sign a written informed consent document.

Exclusion criteria

* An inability to lie still for the tests * Individuals weighing more than 300 lb. (this is the weight limit of the scanner table) * Pregnant or lactating. Women of childbearing potential with either a positive or no pregnancy test at baseline are excluded. * Any other life-threatening illness (e.g. serious, uncontrolled concurrent infection or clinically significant cardiac disease - congestive heart failure, symptomatic coronary artery disease, cardiac arrhythmia not well controlled with medication). * Use of tamoxifen, faslodex, DES or any other ER blocking agent \< 6 weeks or chemotherapy \< 3 weeks prior to imaging scan. * Uncontrolled diabetes mellitus (fasting glucose \> 200 mg/dL) * Adult patients who require monitored anesthesia for PET scanning.

Design outcomes

Primary

MeasureTime frameDescription
Change in F-18 16 Alpha-fluoroestradiol (FES) Standardized Uptake Value (SUV) - Avg SULmaxFrom time of first F-18 FES-PET/CT scan to time of second F-18 FES-PET/CT scan (approximately 1-12 weeks)FES uptake will be quantified using lean body mass adjusted SUV (SUL). Percentage change in FES average SULmax between baseline and a second FES scan will be calculated for up to 3 lesions per patient.
F-18 16 Alpha-fluoroestradiol (FES) UptakeFrom time of first F-18 FES-PET/CT scan to time of second F-18 FES-PET/CT scan (approximately 1-12 weeks)Quantitative measures of FES uptake for each disease site will be determined by drawing regions-of-interest on lesions to determine maximal FES uptake (SUVmax) per lesion. Up to 10 sites seen on the static torso survey will be quantified.
Proportion of Patients With a Threshold of Percentage Change, or That Surpass a Targeted Follow-up F-18 16 Alpha-fluoroestradiol (FES) Standardized Uptake Value (SUV)From time of first F-18 FES-PET/CT scan to time of second F-18 FES-PET/CT scan (approximately 1-12 weeks)The number of patients showing a 20% increase in FES uptake (SULmean or SUVmax) compared to baseline from the first to second scan using a 90% Wilson score binomial confidence interval.

Secondary

MeasureTime frameDescription
Time to Disease ProgressionFrom start of therapy up to 20 yearsTime to disease progression will be measured as the time from the start of endocrine therapy to the time the patient is first recorded as having disease progression.

Countries

United States

Contacts

PRINCIPAL_INVESTIGATORHannah Linden

Fred Hutch/University of Washington Cancer Consortium

Participant flow

Participants by arm

ArmCount
Diagnostic (F-18 FES PET/CT)
Patients undergo F-18 FES PET/CT scan at baseline. Patients also undergo F-18 FES PET/CT and FDG PET/CT between 1-12 weeks after starting therapy. Repeat FDG PET may be omitted in patients on selective estrogen receptor degrader.
2
Total2

Baseline characteristics

CharacteristicDiagnostic (F-18 FES PET/CT)
Age, Categorical
<=18 years
0 Participants
Age, Categorical
>=65 years
2 Participants
Age, Categorical
Between 18 and 65 years
0 Participants
Age, Continuous71 years
Ethnicity (NIH/OMB)
Hispanic or Latino
0 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
2 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
Race (NIH/OMB)
Asian
0 Participants
Race (NIH/OMB)
Black or African American
0 Participants
Race (NIH/OMB)
More than one race
0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
White
2 Participants
Region of Enrollment
United States
2 participants
Sex: Female, Male
Female
2 Participants
Sex: Female, Male
Male
0 Participants

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
0 / 2
other
Total, other adverse events
0 / 2
serious
Total, serious adverse events
0 / 2

Outcome results

Primary

Change in F-18 16 Alpha-fluoroestradiol (FES) Standardized Uptake Value (SUV) - Avg SULmax

FES uptake will be quantified using lean body mass adjusted SUV (SUL). Percentage change in FES average SULmax between baseline and a second FES scan will be calculated for up to 3 lesions per patient.

Time frame: From time of first F-18 FES-PET/CT scan to time of second F-18 FES-PET/CT scan (approximately 1-12 weeks)

Population: 2 patients had 2 FES scans each

ArmMeasureValue (MEAN)
Diagnostic (F-18 FES PET/CT)Change in F-18 16 Alpha-fluoroestradiol (FES) Standardized Uptake Value (SUV) - Avg SULmax78 Percentage decrease in avgSUL
Primary

F-18 16 Alpha-fluoroestradiol (FES) Uptake

Quantitative measures of FES uptake for each disease site will be determined by drawing regions-of-interest on lesions to determine maximal FES uptake (SUVmax) per lesion. Up to 10 sites seen on the static torso survey will be quantified.

Time frame: From time of first F-18 FES-PET/CT scan to time of second F-18 FES-PET/CT scan (approximately 1-12 weeks)

Population: 2 patients had 2 scans each

ArmMeasureGroupValue (MEAN)
Diagnostic (F-18 FES PET/CT)F-18 16 Alpha-fluoroestradiol (FES) UptakeFES scan 15.7 average SUVmax
Diagnostic (F-18 FES PET/CT)F-18 16 Alpha-fluoroestradiol (FES) UptakeFES scan 21.4 average SUVmax
Primary

Proportion of Patients With a Threshold of Percentage Change, or That Surpass a Targeted Follow-up F-18 16 Alpha-fluoroestradiol (FES) Standardized Uptake Value (SUV)

The number of patients showing a 20% increase in FES uptake (SULmean or SUVmax) compared to baseline from the first to second scan using a 90% Wilson score binomial confidence interval.

Time frame: From time of first F-18 FES-PET/CT scan to time of second F-18 FES-PET/CT scan (approximately 1-12 weeks)

Population: 2 patients had 2 FES scans each

ArmMeasureValue (NUMBER)
Diagnostic (F-18 FES PET/CT)Proportion of Patients With a Threshold of Percentage Change, or That Surpass a Targeted Follow-up F-18 16 Alpha-fluoroestradiol (FES) Standardized Uptake Value (SUV)0 participants with increased FES uptake
Secondary

Time to Disease Progression

Time to disease progression will be measured as the time from the start of endocrine therapy to the time the patient is first recorded as having disease progression.

Time frame: From start of therapy up to 20 years

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026