NCT07661927

Brief Summary

The goal of this clinical trial is to determine whether a selected population of women with early-stage, low-risk breast cancer can avoid hormone therapy without increasing their risk of relapse. It will also evaluate the prognosis of these participants compared to participants who received standard treatment with hormone therapy in another study, estimate the risk of specific recurrence, cardiovascular and bone health, and participants' quality of life. All participants will have undergone surgery and possibly radiation therapy, but unlike standard care, they will not receive hormone therapy afterward. Participants will be enrolled for two years and followed for up to five years after the last participant is enrolled in the trial to monitor for long-term cancer recurrence.

Trial Health

77
On Track

Trial Health Score

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

Enrollment
700

participants targeted

Target at P75+ for phase_2

Timeline
84mo left

Started Jul 2026

Longer than P75 for phase_2

Geographic Reach
1 country

41 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 Progress1%
Jul 2026Jul 2033

First Submitted

Initial submission to the registry

May 22, 2026

Completed
1 month until next milestone

First Posted

Study publicly available on registry

June 22, 2026

Completed
14 days until next milestone

Study Start

First participant enrolled

July 6, 2026

Completed
7 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

July 6, 2033

Expected
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

July 6, 2033

Last Updated

July 17, 2026

Status Verified

May 1, 2026

Enrollment Period

7 years

First QC Date

May 22, 2026

Last Update Submit

July 16, 2026

Conditions

Keywords

breast cancerhormone therapyde-escalation

Outcome Measures

Primary Outcomes (1)

  • Relapse-free interval

    Relapse-free interval (RFI) is defined as the delay between initial treatment and the first occurrence of i) ipsilateral breast tumor recurrence, ii) distant or locoregional recurrence or iii) death from breast cancer, according to the STEEP system definition version 2.0 (Tolaney SM et al., J Clin Oncol 2021)

    At 5 years after the last treatment

Secondary Outcomes (9)

  • Incidence of Ipsilateral Ductal Carcinoma In Situ (DCIS)

    At 5 years after the last treatment

  • Incidence of invasive contralateral breast cancer

    At 5 years after the last treatment

  • Distant disease free survival (DDFS)

    At 5 years after the last treatment

  • Relapse free survival (RFS)

    5 years after the last treatment

  • Overall survival (OS)

    At 5 years after the last treatment

  • +4 more secondary outcomes

Study Arms (1)

No Endocrine Therapy

EXPERIMENTAL

The endocrine therapy will not be received by the participant during the study.

Drug: Removing Endocrine Therapy

Interventions

The standard of care endocrine therapy (Tamoxifene, Letrozole, Anastrozole or Exemestane) will not be received by the participant during the study.

No Endocrine Therapy

Eligibility Criteria

Age60 Years+
Sexfemale
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Postmenopausal (underwent bilateral oophorectomy or non-chemo induced amenorrhea for 12 or more months) female participant ≥60 years of age.
  • New diagnosis of invasive carcinoma of the breast (ductal, tubular or mucinous) with primary tumor ≤1 cm on microscopic exam with no evidence of nodal or distant metastatic disease.
  • Contralateral breast described as BI-RADS (Breast Imaging-Reporting And Data System) 1 or 2 in diagnostic imaging.
  • Negative axillary node involvement by sentinel node biopsy or axillary node dissection (pN0) or Clinically negative axillary node involvement (cN0) after mandatory ultrasound exploration without surgical exploration of the axilla if Breast Conservative Surgery (BCS) was performed.
  • Estrogen Receptor (ER) positive (≥ 50%) and Progesterone Receptor(PR) positive (\> 20%), Ki67 low (≤15%) and HER2 negative (IHC or In Situ Hybridization approach) according to ASCO (American Society of Clinical Oncology) criteria.
  • Histological grade scored on the invasive component, 1 or 2 if pT1a or grade 1 if pT1b.
  • Treated by mastectomy or BCS with microscopically clear resection margins defined as "no-ink on tumor" or ≥1 mm for invasive and non-invasive disease or no residual disease on re-excision.
  • If BCS was performed, participants must have received or have scheduled adjuvant local radiotherapy (RT) within 3 months after surgery
  • No indication of adjuvant chemotherapy.
  • The participant is willing and able to comply with the protocol for the duration of the study, including scheduled visits, treatment strategy, laboratory tests and other study procedures.
  • Participants must be affiliated with a Social Security System (or equivalent).
  • The participant must have signed a written informed consent form before any trial-specific procedures. When the participant is physically unable to give written consent, an impartial witness of her choice, independent from the investigator or the sponsor, can confirm the participant's consent in writing.

You may not qualify if:

  • Have received any neo-adjuvant treatment, including hormone therapy and chemotherapy.
  • Have received or are eligible for adjuvant chemotherapy.
  • Absolute contraindication for RT in case of BCS or patients who were treated with partial breast irradiation.
  • Have been treated with mastectomy and with adjuvant radiotherapy received or scheduled.
  • Invasive lobular breast cancer.
  • Bilateral breast cancer or history of other invasive ipsi- or contralateral breast cancer.
  • Multifocal or multicentric disease.
  • Disease limited to microinvasion only (\< 1 mm).
  • Evidence of lymphovascular invasion.
  • History of non-breast cancer malignancies if not disease-free for \> 5 years and considered low risk of recurrence except for treated carcinoma in situ of the cervix, endometrium or colon, melanoma in situ and basal or squamous cell carcinoma of the skin.
  • Non-malignant severe disease associated with a life expectancy \< 10 years.
  • Women with BRCA1, BRCA2 or other high-risk breast cancer predisposing deleterious germline mutations.
  • Unwilling or unable to comply with the medical follow-up required by the trial because of geographic, familial, social, or psychological reasons.
  • Persons deprived of their liberty or under protective custody or guardianship.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (41)

Ico Angers

Angers, France

NOT YET RECRUITING

Sainte Catherine, Institut du Cancer Avignon-Provence

Avignon, France

NOT YET RECRUITING

CH Aunay-Bayeux

Bayeux, France

NOT YET RECRUITING

CHCB

Bayonne, France

NOT YET RECRUITING

Clinique Tivoli

Bordeaux, France

NOT YET RECRUITING

Institut Bergonié

Bordeaux, France

NOT YET RECRUITING

CH Boulogne sur mer

Boulogne-sur-Mer, France

NOT YET RECRUITING

Clinique Pasteur Lanroze

Brest, France

NOT YET RECRUITING

CH de Bligny

Briis-sous-Forges, France

NOT YET RECRUITING

Centre Francois Baclesse

Caen, France

NOT YET RECRUITING

Pole Sante Leonard de Vinci- Roc37

Chambray-lès-Tours, France

NOT YET RECRUITING

Centre Jean Perrin

Clermont-Ferrand, France

NOT YET RECRUITING

Centre Leonard de Vinci

Dechy, France

NOT YET RECRUITING

Centre Georges François Leclerc

Dijon, France

NOT YET RECRUITING

CH Annecy Genevois

Épagny, France

ACTIVE NOT RECRUITING

CHD Vendée

La Roche-sur-Yon, France

NOT YET RECRUITING

Centre Guillaume le Conquérant

Le Havre, France

ACTIVE NOT RECRUITING

Centre Oscar Lambret

Lille, France

ACTIVE NOT RECRUITING

CHU de Limoges

Limoges, France

NOT YET RECRUITING

Groupe Hospitalier Bretagne Sud

Lorient, France

RECRUITING

Centre Léon Bérard

Lyon, France

ACTIVE NOT RECRUITING

Hôpital privé Jean Mermoz

Lyon, France

NOT YET RECRUITING

Hôpital Privé Clairval

Marseille, France

NOT YET RECRUITING

Institut Paoli-Calmettes

Marseille, France

NOT YET RECRUITING

CHI de Mont-de-Marsan

Mont-de-Marsan, France

ACTIVE NOT RECRUITING

Centre Antoine Lacassagne

Nice, France

NOT YET RECRUITING

CHU Orleans

Orléans, France

NOT YET RECRUITING

CHP Sainte Marie

Osny, France

NOT YET RECRUITING

Groupe Hospitalier Paris Saint Joseph

Paris, France

NOT YET RECRUITING

Institut Curie

Paris, France

ACTIVE NOT RECRUITING

Centre Eugène Marquis

Rennes, France

NOT YET RECRUITING

Centre Henri Becquerel

Rouen, France

NOT YET RECRUITING

Institut Curie

Saint-Cloud, France

NOT YET RECRUITING

Ico Saint Herblain

Saint-Herblain, France

NOT YET RECRUITING

CHU de Saint Etienne

Saint-Priest-en-Jarez, France

NOT YET RECRUITING

Centre de lutte contre le cancer - Paul Strauss

Strasbourg, France

NOT YET RECRUITING

Hôpitaux du Léman

Thonon-les-Bains, France

NOT YET RECRUITING

IUCT-Oncopole

Toulouse, France

NOT YET RECRUITING

CHU Tours

Tours, France

NOT YET RECRUITING

Institut de Cancérologie de Lorraine

Vandœuvre-lès-Nancy, France

NOT YET RECRUITING

Groupe UNEOS-Hôpital Robert Schuman

Vantoux, France

NOT YET RECRUITING

MeSH Terms

Conditions

Breast Neoplasms

Condition Hierarchy (Ancestors)

Neoplasms by SiteNeoplasmsBreast DiseasesSkin DiseasesSkin and Connective Tissue Diseases

Study Officials

  • Jean-Yves PIERGA, MD

    Institut Curie

    PRINCIPAL INVESTIGATOR
  • José Luis SANDOVAL, MD

    University Hospital, Geneva

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Unicancer Project Leader

CONTACT

Study Design

Study Type
interventional
Phase
phase 2
Allocation
NA
Masking
NONE
Purpose
TREATMENT
Intervention Model
SINGLE GROUP
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

May 22, 2026

First Posted

June 22, 2026

Study Start

July 6, 2026

Primary Completion (Estimated)

July 6, 2033

Study Completion (Estimated)

July 6, 2033

Last Updated

July 17, 2026

Record last verified: 2026-05

Data Sharing

IPD Sharing
Will not share

Individual Participant Data will not be shared at an individual level. Those data will be part of the study database including all enrolled patients.

Locations