Using PET imaging to assess treatment response in metastatic ER+ breast cancer

Dynamic and Test-retest Whole Body [18F]FES PET Imaging in Patients With Metastatic ER+ Breast Cancer

Not applicable Interventional Amsterdam UMC, location VUmc · NCT05088785

This study is testing a special imaging technique to see if it can help doctors understand how well treatments are working for patients with metastatic ER+ breast cancer.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment15 (estimated)
Ages18 Years and up
SexFemale
SponsorAmsterdam UMC, location VUmc Academic / other
Locations1 site (Amsterdam, North-Holland)
Trial IDNCT05088785 on ClinicalTrials.gov

What this trial studies

This study investigates the use of 18F-fluoro-17b-estradiol (18F-FES) PET imaging to visualize estrogen receptor expression in patients with metastatic ER+ breast cancer. The primary aim is to establish 18F-FES PET as a diagnostic imaging biomarker for assessing treatment response, moving beyond its current role as a diagnostic tool. The study will derive an optimal pharmacokinetic model for quantitative analysis of 18F-FES uptake and evaluate simplified parameters for clinical feasibility. A total of five patients will be assessed to validate these approaches.

Who should consider this trial

Good fit: Ideal candidates include postmenopausal females aged 18 or older with histologically confirmed metastatic ER+ breast cancer.

Not a fit: Patients with liver metastases or those who do not meet the inclusion criteria may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide a more accurate method for monitoring treatment response in patients with metastatic ER+ breast cancer.

How similar studies have performed: Other studies have explored the use of PET imaging in cancer diagnostics, indicating potential success for similar approaches.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Histologically proven metastatic ER+ (\>10% positive stained cells using immunohistochemistry) breast cancer on the latest biopsy
* Postmenopausal females aged 18 years or older at screening. Postmenopausal status is defined as one of the following:

  1. age ≥60 years
  2. age \<60 years and amenorrhea for \>12 months in the absence of interfering hormonal therapies (such as LH-RH agonists and ER-antagonists)
  3. patient age \<60 years using LH-RH agonists should continue LH- RH-agonists until after the PET procedures
  4. previous bilateral oophorectomy or medically confirmed ovarian failure
* \[18F\]FDG PET, CT and/or a bone scan should be performed as part of routine clinical staging (≤4 weeks prior to screening)
* Patients should have metastases in the scanning field of view, all located outside of the liver
* Eastern Cooperative Oncology Group Performance Status (ECOG PS) of 0-2
* Estimated glomerular filtration rate (eGFR) ≥30 ml/min
* Written and signed informed consent

Exclusion Criteria:

* History with another cancer within the last 5 years, except cancer treated with curative intent and no evidence of disease as judged by the treating physician
* Use of selective estrogen receptor modulators (SERMs) or downregulators (SERDs) for current breast cancer such as Tamoxifen/Fulvestrant (≤5 weeks prior to screening) or investigational drug therapy
* Pregnancy or lactating women
* Any medical, psychological or social condition that may interfere with the subject's safety and participation in the study, will lead to exclusion from this study

Where this trial is running

Amsterdam, North-Holland

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Breast Cancer
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.