NCT06877949

Brief Summary

Several studies have shown improved sensitivity of FDG-PET/CT compared with conventional imaging for diagnosing metastatic breast cancer in retrospective and smaller prospective studies. For response monitoring, we expect FDG-PET/CT to detect disease progression earlier than CT in patients treated for metastatic breast cancer, enabling earlier start of second-line therapies. Current knowledge about the potential benefit of FDG-PET/CT for response monitoring of patients with metastatic breast cancer comes from observational studies. Consequently, current evidence is only hypothesis-generating and prospective, randomized trials such as the MONITOR-RCT are needed to corroborate these findings. The MONITOR-RCT clinical trial aims to investigate whether monitoring with FDG-PET/CT can improve survival in patients diagnosed with metastatic breast cancer. It is a parallel group comparative randomized trial comparing an experimental monitoring strategy based on FDG-PET/CT with a standard monitoring strategy based on CT. Participating patients should have newly diagnosed metastatic breast cancer and be considered eligible for initiating first-line medical treatment and subsequent regular response monitoring. A total of 420 patients will be included in the study, with recruitment taking place across 11 participating hospital sites in Denmark, Germany, and Italy. The main questions it aims to answer are:

  • Can monitoring with FDG-PET/CT compared to conventional CT prolong the overall survival of MBC patients?
  • Is this-as expected-due to earlier detection of disease progression and earlier initiation of second-line therapies?
  • Is this accompanied by less need for additional diagnostics, less need for hospitalization, and improved quality of life? Participants will:
  • Undergo FDG-PET/CT scans at scheduled intervals to monitor disease progression.
  • Be given standard treatments as part of oncological care, which is informed by the FDG-PET/CT scans
  • Fill out questionnaires about their quality of life at various time points throughout the study. Objectives are: Primary: To demonstrate superiority in overall survival of response monitoring with FDG-PET/CT in patients with metastatic breast cancer over response monitoring based on CT. Appropriately adapted PERCIST criteria for FDG-PET/CT and the RECIST1.1 criteria for CT will be used. Secondary: To demonstrate superiority in quality of life and exposure to oncologic treatment with FDG-PET/CT and to investigate the cost-effectiveness.

Trial Health

80
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
420

participants targeted

Target at P75+ for not_applicable

Timeline
36mo left

Started Apr 2025

Longer than P75 for not_applicable

Geographic Reach
3 countries

11 active sites

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Progress27%
Apr 2025Apr 2029

First Submitted

Initial submission to the registry

February 21, 2025

Completed
21 days until next milestone

First Posted

Study publicly available on registry

March 14, 2025

Completed
19 days until next milestone

Study Start

First participant enrolled

April 2, 2025

Completed
4 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

April 1, 2029

Expected
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

April 1, 2029

Last Updated

February 20, 2026

Status Verified

December 1, 2025

Enrollment Period

4 years

First QC Date

February 21, 2025

Last Update Submit

February 19, 2026

Conditions

Keywords

Metastatic Breast CancerResponse MonitoringFDG-PET/CTSurvivalProgression

Outcome Measures

Primary Outcomes (1)

  • Overall survival

    Time from randomization until death for any reason

    From date of randomization until the date of death assessed up to 54 months.

Secondary Outcomes (10)

  • Quality of life: FACT-B

    Measured at baseline, after 3, 6, 9, 12, 18, 24, 30, 36, 42, 48 and 54 months - if the patient is still alive. Average over all time points wil be reported.

  • Quality of Life: Patient complaints

    Assessed at baseline, after 3, 6, 9, 12, 18, 24, 30, 36, 42, 48 and 54 months - if the patient is still alive. Reporting will not be time point specific.

  • Experience of progression

    The corresponding events will be continuously documented from randomization for up to 54 months.

  • Start of a new treatment line due to progression

    The corresponding events will be continuously documented from randomization for up to 54 months.

  • Time to first progression

    From date of randomization until the date of first documented progression assessed up to 54 months.

  • +5 more secondary outcomes

Study Arms (2)

FDG-PET/CT

EXPERIMENTAL

Monitoring of patients with FDG-PET/CT

Diagnostic Test: FDG-PET/CT

CT

ACTIVE COMPARATOR

Monitoring of patients with current standard.

Diagnostic Test: CE-CT

Interventions

CE-CTDIAGNOSTIC_TEST

CE-CT is used regulary for a continuous, long-term monitoring

CT
FDG-PET/CTDIAGNOSTIC_TEST

FDG-PET/CT is used regulary for a continuous, long term monitoring

FDG-PET/CT

Eligibility Criteria

Age18 Years+
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Women and men aged ≥18 years
  • Diagnosis of distant relapsed MBC (biopsy-verified) or de novo breast cancer. In patients with distant relapsed MBC, biopsy verification from a distant metastasis is required. In patients with de novo MBC, biopsy verification of primary tumor and diagnostic imaging with distant metastasis with a typical pattern of MBC is required.
  • Considered eligible for first-line systemic treatment
  • Considered eligible for continuous treatment monitoring by scans.
  • Signed informed consent
  • Participants must have the ability to read and understand the following languages based on their country of participation: in Denmark, patients must be able to read and understand Danish; in Italy, they must be able to read and understand Italian or English; and in Germany, they must be able to read and understand German or English.
  • In case of patients for whom it is necessary to start first-line systemic treatment while still waiting for the evaluation of the biopsy, it is allowed to include the patients, as long as the other criteria are fulfilled and the biopsy is made or planned. In case verification by biopsy fails, the patients will leave the trial (cf. 4c). We expect that up to 3% of the patients included will start first-line systemic treatment prior to evaluation of the biopsy

You may not qualify if:

  • Pregnant or lactating women
  • Ongoing oncological treatment for another cancer
  • Exclusively brain metastasis
  • Allergy to FDG

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (11)

Aalborg University Hospital

Aalborg, 9000, Denmark

RECRUITING

Aarhus University Hospital

Aarhus, 8200, Denmark

RECRUITING

Rigshospitalet

Copenhagen, 2100, Denmark

RECRUITING

Esbjerg and Grindsted Hospital

Esbjerg, 6700, Denmark

RECRUITING

Herlev and Gentofte Hospital

Herlev, 2730, Denmark

RECRUITING

Odense University Hospital

Odense, 5000, Denmark

RECRUITING

Hospital of Southern Jutland

Sønderborg, 6400, Denmark

RECRUITING

Lille Baelt Hospital

Vejle, 7100, Denmark

RECRUITING

Klinikum Der Technischen Universität München

München, 81675, Germany

NOT YET RECRUITING

Irccs Azienda Ospedaliero - Universitario Di Bologna

Bologna, 40138, Italy

RECRUITING

Humanitas Research Hospital

Milan, 20089, Italy

NOT YET RECRUITING

Related Publications (2)

  • Naghavi-Behzad M, Vogsen M, Vester RM, Olsen MMB, Oltmann H, Braad PE, Asmussen JT, Gerke O, Vach W, Kidholm K, Kodahl AR, Weber W, Hildebrandt MG. Response monitoring in metastatic breast cancer: a comparison of survival times between FDG-PET/CT and CE-CT. Br J Cancer. 2022 May;126(9):1271-1279. doi: 10.1038/s41416-021-01654-w. Epub 2022 Jan 10.

    PMID: 35013575BACKGROUND
  • Vogsen M, Harbo F, Jakobsen NM, Nissen HJ, Dahlsgaard-Wallenius SE, Gerke O, Jensen JD, Asmussen JT, Jylling AMB, Braad PE, Vach W, Ewertz M, Hildebrandt MG. Response Monitoring in Metastatic Breast Cancer: A Prospective Study Comparing 18F-FDG PET/CT with Conventional CT. J Nucl Med. 2023 Mar;64(3):355-361. doi: 10.2967/jnumed.121.263358. Epub 2022 Oct 7.

    PMID: 36207136BACKGROUND

MeSH Terms

Conditions

Breast NeoplasmsDisease Progression

Condition Hierarchy (Ancestors)

Neoplasms by SiteNeoplasmsBreast DiseasesSkin DiseasesSkin and Connective Tissue DiseasesDisease AttributesPathologic ProcessesPathological Conditions, Signs and Symptoms

Study Officials

  • Malene G Hildebrandt, MD, Professor

    Odense University Hospital

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Malene G Hildebrandt, MD, Professor

CONTACT

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
NONE
Purpose
DIAGNOSTIC
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

February 21, 2025

First Posted

March 14, 2025

Study Start

April 2, 2025

Primary Completion (Estimated)

April 1, 2029

Study Completion (Estimated)

April 1, 2029

Last Updated

February 20, 2026

Record last verified: 2025-12

Data Sharing

IPD Sharing
Will share

While most of the data itself will not be publicly accessible due to its sensitive nature metadata will be made openly accessible in well-known open repositories under controlled access where applicable. Detailed information about data access conditions will be included, specifying that data is available only under strict ethical and legal guidelines, with access requests subject to approval by ethics committees and data-use agreements as mandated by GDPR and national regulations.

Shared Documents
STUDY PROTOCOL, SAP
Time Frame
The possibility to apply for IPD data access will be opened after end of the study.
Access Criteria
Cr. the plan description given above.

Locations