Recruiting
Phase 2

Neoadjuvant Endocrine Therapy

Sponsor:

Memorial Sloan Kettering Cancer Center

Code:

NCT07483307

Conditions

Breast Cancer

HER2-negative Breast Cancer

HER2 Negative Breast Carcinoma

ER+ Breast Cancer

Lobular Breast Carcinoma

Eligibility Criteria

Sex: Female

Age: 50+

Healthy Volunteers: Not accepted

Interventions

Neoadjuvant endocrine therapy

Study Details

Brief summary:

The purpose of this study is to look at how effective neoadjuvant (before surgery) endocrine therapy (NET) is in participants with invasive lobular carcinoma (ILC) who have breast-conserving surgery (BCS). The main purpose of the study is to see if NET reduces the chance of having cancer cells at the edges of tissue removed during surgery (positive margins).

Conditions

Breast Cancer

HER2-negative Breast Cancer

HER2 Negative Breast Carcinoma

ER+ Breast Cancer

Lobular Breast Carcinoma

Study ID

NCT07483307

Start date

Mar 13, 2026

Status verified date

Jun, 2026

Completion date

Mar 13, 2030

Anticipated

Primary completion date

Mar 13, 2030

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: Female

Age: 50+

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • Written informed consent by participant or legally authorized representative
  • Postmenopausal women aged ≥50 years with biopsy-proven cT2-T3 N0-1 ILC who opt to undergo and are medically fit to undergo BCS at enrollment.
  • Tumors of the ER+/HER2- subtype, defined as:

1. ER+: Positive for ER staining as indicated by ≥10% immunoreactive tumor nuclei.
2. HER2-: Immunohistochemistry assay demonstrating no or faint staining in ≤10% of tumor cells (IHC 0 or 1+) or negative by dual probe in situ hybridization assay.

Exclusion Criteria:

  • Patients with prior ipsilateral breast cancer.
  • Patients with advanced regional disease (cN2/cN3) or stage 4 disease.
  • Patients who would benefit from neoadjuvant chemotherapy, per the treating medical oncologist.
  • Patients who are not candidates for definitive breast surgery (inoperable or stage 4 disease).
  • Patients with gadolinium allergy, precluding the use of breast MRI.

Study Design

Enrollment

176 participants

Anticipated

Intervention Model

Single group

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Participants with ER+/HER2- Breast Cancer

Participants will be postmenopausal women aged ≥50 years with biopsy-proven cT2-T3 N0-1 ILC, ER+/HER2- subtype

Interventions

Neoadjuvant endocrine therapy

The endocrine therapy used for the NET in this study will be anastrozole, letrozole, exemestane, or tamoxifen.

Primary outcome measure

  • Rate of positive surgical margins after breast cancer surgery [ Time Frame: up to 3 months ]

Central Contacts and Locations

Central contacts

Anita Mamtani, MD

646-888-6864mamtana1@mskcc.org

George Plitas, MD

646-888-5368PlitasG@mskcc.org

Locations

Memorial Sloan Kettering Basking Ridge (Limited Protocol Activities)

Recruiting

Basking Ridge, New Jersey, United States, 07920

Contacts

Anita Mamtani, MD

646-888-6864

Memorial Sloan Kettering Monmouth (Limited Protocol Activities)

Recruiting

Middletown, New Jersey, United States, 07748

Contacts

Anita Mamtani, MD

646-888-6864

Memorial Sloan Kettering Bergen (Limited Protocol Activities)

Recruiting

Montvale, New Jersey, United States, 07645

Contacts

Anita Mamtani, MD

646-888-6864

Memorial Sloan Kettering Suffolk - Commack (Limited Protocol Activities)

Recruiting

Commack, New York, United States, 11725

Contacts

Anita Mamtani, MD

646-888-6864

Memorial Sloan Kettering Westchester (Limited Protocol Activities)

Recruiting

Harrison, New York, United States, 10604

Contacts

Anita Mamtani, MD

646-888-6864

Memorial Sloan Kettering Cancer Center (All Protocol Activities)

Recruiting

New York, New York, United States, 10065

Contacts

Anita Mamtani, MD

646-888-6864

Memorial Sloan Kettering Nassau (Limited Protocol Activities)

Recruiting

Uniondale, New York, United States, 11553

Contacts

Anita Mamtani, MD

646-888-6864

More Information

Sponsor

Memorial Sloan Kettering Cancer Center

Last update posted

Jun 4, 2026

Last verified

Jun, 2026

Keywords

  • Breast Cancer
  • HER2-negative Breast Cancer
  • HER2 Negative Breast Carcinoma
  • ER+ Breast Cancer
  • 26-095
  • Memorial Sloan Kettering Cancer Center
  • Lobular Breast Cancer

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Memorial Sloan Kettering Cancer Center on 2026-06-04.