Radiation OmisSion in PAtients With CLinically Node Negative Breast Cancer Undergoing Lumpectomy

NCT05866458 | Recruiting DMC

• 1 other identifier: OCOG-2022-ROSALIE
• Study Type: observational
• Target: 352
• Locations: 1 country
• Sites: 12

Brief Summary

To de-escalate radiation therapy in women with breast cancer.

Conditions

Breast Cancer

Keywords

Clinically node negative breast cancer; Ipsilateral breast tumour recurrence; Neoadjuvant chemotherapy

Outcome Measures

Primary Outcomes (1)

• Ipsilateral breast tumour recurrence (IBTR)

  defined as ipsilateral recurrence (invasive or insitu) in the ipsilateral breast or chest wall. Histological evidence of IBTR is required. All such events will be reviewed by a central adjudication committee.

  5 years

Secondary Outcomes (4)

• Mastectomy free interval

  5 years

• Relapse free interval (RFI)

  5 years

• Disease free survival (DFS)

  5 years

• Overall survival (OS)

  5 years

Study Arms (1)

Single Arm Cohort

The study population consists of women with newly diagnosed T1-3 node negative breast cancer with no clinical evidence of distant metastatic disease, that have been treated with NAC, BCS and axillary staging surgery with final pathology demonstrating a pCR (defined as absence of residual invasive and in situ breast cancer within the breast or lymph nodes).

Eligibility Criteria

• Age: 50 Years+
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Written informed consent will be obtained from all eligible patients who agree to participate. Until the patient has been completely informed of the study, has freely consented to take part in the study and has signed and dated an informed consent form that has received documented approval by an authorized Research Ethics Board (REB), no study related assessments, including those required for screening can be performed.

You may qualify if:

• Female patient with a new histological diagnosis of clinical T1-3 N0 breast cancer (any tumour sub-type).
• Negative lymph node involvement at initial presentation, documented by imaging (US or MRI), fine needle aspiration (FNA) or core needle biopsy.
• Treated with a minimum of 8 weeks NAC, with patients with Her2+ disease receiving targeted anti-Her2+ therapy.
• Marker clip placed in the tumour bed prior to or during neoadjuvant chemotherapy when the tumour can still be identified.
• Treated by BCS with complete excision of the tumour bed and axillary staging surgery (either sentinel lymph node biopsy or axillary lymph node dissection).
• Final pathology demonstrating a pCR \[defined as absence of residual invasive and in-situ breast cancer within the breast or lymph nodes (ypT0N0)\].

You may not qualify if:

• Age less than 50 years.
• Inflammatory breast cancer or breast cancer invading the skin or chest wall (T4 disease).
• Multicentric disease (i.e., breast cancer involving more than one quadrant in the same breast).
• Prior history of ipsilateral or contralateral in-situ or invasive breast cancer. Patients with a history of lobular carcinoma in-situ (LCIS) are ineligible.
• Synchronous contralateral in-situ or invasive breast cancer.
• BRCA (breast cancer gene) 1 or 2 genetic mutation carrier, or other genetic mutation present associated with increased risk of breast cancer.
• Other previous non-breast malignancies except adequately treated non-melanoma skin cancers, in situ cancers or other cancers curatively treated with no evidence of disease for ≥ 5 years.
• Inability to complete entire course of neoadjuvant therapy (minimum of 8 weeks of treatment).
• Patients with HR+ (hormone receptor) disease who are not planned to have endocrine therapy initiated.
• Patients with Her2+ disease who have not received or are not planned to receive Her2 targeted therapy.
• ECOG (Eastern Cooperative Oncology Group) performance status \> 3.
• Inability to provide informed consent.

Sponsors & Collaborators

• Ontario Clinical Oncology Group (OCOG): lead

Study Sites (12)

BC Cancer - Centre for the North

Prince George, British Columbia, V2M 7E9, Canada

RECRUITING

Royal Victoria Regional Health Centre

Barrie, Ontario, L4M 6M2, Canada

RECRUITING

Juravinski Cancer Centre

Hamilton, Ontario, L8V 5C2, Canada

RECRUITING

Cancer Centre of Southeastern Ontario at Kingston

Kingston, Ontario, K7L 5P9, Canada

RECRUITING

Thunder Bay Regional Health Sciences Centre

Thunder Bay, Ontario, P7B 6V4, Canada

RECRUITING

Sunnybrook Health Sciences -Odette Cancer Centre

Toronto, Ontario, M4N 3M5, Canada

RECRUITING

CHUM - Centre Hospitalier de L'Université de Montréal

Montreal, Quebec, H2L 4M1, Canada

RECRUITING

Jewish General Hospital

Montreal, Quebec, H3T 1E2, Canada

RECRUITING

CHU de Quebec - Universite Laval

Québec, Quebec, G1R 2J6, Canada

RECRUITING

Centre hospitalier de Lanaudière

Saint-Charles-Borromée, Quebec, J6E 6J2, Canada

RECRUITING

Centre Hospitalier Trois Rivieres Ste-Marie

Trois-Rivières, Quebec, G8Z 3R9, Canada

RECRUITING

McGill University Health Centre (MUHC)

Montreal, Q, H4A 3J1, Canada

RECRUITING

MeSH Terms

Conditions

Breast Neoplasms

Condition Hierarchy (Ancestors)

Neoplasms by Site; Neoplasms; Breast Diseases; Skin Diseases; Skin and Connective Tissue Diseases

Study Officials

• Elena Parvez, MD

  Juravinski Cancer Centre

  PRINCIPAL INVESTIGATOR

• Thierry Muanza, MD

  Jewish General Hospital

  PRINCIPAL INVESTIGATOR

• Mark Basik, MD

  Jewish General Hospital

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Adrianne Van Dam

CONTACT

905-527-2299; avandam@mcmaster.ca

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 10, 2023
• First Posted: May 19, 2023
• Study Start: March 12, 2024
• Primary Completion (Estimated): October 1, 2031
• Study Completion (Estimated): October 1, 2031
• Last Updated: November 18, 2025

Record last verified: 2025-09

Data Sharing

• IPD Sharing: Will not share

Locations

CA (12)