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Recruiting NCT05866458

NCT05866458 Radiation OmisSion in PAtients With CLinically Node Negative Breast Cancer Undergoing Lumpectomy

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Clinical Trial Summary
NCT ID NCT05866458
Status Recruiting
Phase
Sponsor Ontario Clinical Oncology Group (OCOG)
Condition Breast Cancer
Study Type OBSERVATIONAL
Enrollment 352 participants
Start Date 2024-03-12
Primary Completion 2031-10

Eligibility & Interventions

Sex Female only
Min Age 50 Years
Max Age N/A
Study Type OBSERVATIONAL

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

This is an observational study. You will not receive an experimental treatment; researchers will collect data based on your existing condition or standard treatment.

This trial targets 352 participants in total. It began in 2024-03-12 with a primary completion date of 2031-10.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

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

Eligibility Criteria

Inclusion Criteria: 1. Female patient with a new histological diagnosis of clinical T1-3 N0 breast cancer (any tumour sub-type). 2. Negative lymph node involvement at initial presentation, documented by imaging (US or MRI), fine needle aspiration (FNA) or core needle biopsy. 3. Treated with a minimum of 8 weeks NAC, with patients with Her2+ disease receiving targeted anti-Her2+ therapy. 4. Marker clip placed in the tumour bed prior to or during neoadjuvant chemotherapy when the tumour can still be identified. 5. Treated by BCS with complete excision of the tumour bed and axillary staging surgery (either sentinel lymph node biopsy or axillary lymph node dissection). 6. Final pathology demonstrating a pCR \[defined as absence of residual invasive and in-situ breast cancer within the breast or lymph nodes (ypT0N0)\]. Exclusion Criteria: 1. Age less than 50 years. 2. Inflammatory breast cancer or breast cancer invading the skin or chest wall (T4 disease). 3. Multicentric disease (i.e., breast cancer involving more than one quadrant in the same breast). 4. Prior history of ipsilateral or contralateral in-situ or invasive breast cancer. Patients with a history of lobular carcinoma in-situ (LCIS) are ineligible. 5. Synchronous contralateral in-situ or invasive breast cancer. 6. BRCA (breast cancer gene) 1 or 2 genetic mutation carrier, or other genetic mutation present associated with increased risk of breast cancer. 7. 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. 8. Inability to complete entire course of neoadjuvant therapy (minimum of 8 weeks of treatment). 9. Patients with HR+ (hormone receptor) disease who are not planned to have endocrine therapy initiated. 10. Patients with Her2+ disease who have not received or are not planned to receive Her2 targeted therapy. 11. ECOG (Eastern Cooperative Oncology Group) performance status \> 3. 12. Inability to provide informed consent.

Contact & Investigator

Central Contact

Adrianne Van Dam

✉ avandam@mcmaster.ca

📞 905-527-2299

Principal Investigator

Elena Parvez, MD

PRINCIPAL INVESTIGATOR

Juravinski Cancer Centre

Frequently Asked Questions

Who can join the NCT05866458 clinical trial?

This trial is open to female participants only, aged 50 Years or older, studying Breast Cancer. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

Is NCT05866458 currently recruiting?

Yes, NCT05866458 is actively recruiting participants. Contact the research team at avandam@mcmaster.ca for enrollment information.

Where is the NCT05866458 trial being conducted?

This trial is being conducted at Cudgen, Australia, Liverpool, Australia, North Sydney, Australia, Westmead, Australia and 11 additional locations.

Who is sponsoring the NCT05866458 clinical trial?

NCT05866458 is sponsored by Ontario Clinical Oncology Group (OCOG). The principal investigator is Elena Parvez, MD at Juravinski Cancer Centre. The trial plans to enroll 352 participants.

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ClinicalMetric — Independent clinical trial intelligence platform. Not affiliated with NIH, ClinicalTrials.gov, the U.S. FDA, or any pharmaceutical company, hospital, or clinical research organization. Trial data is sourced from ClinicalTrials.gov for informational purposes only and does not constitute medical advice. Do not make any treatment, enrollment, or health decisions based solely on information found here — always consult a qualified healthcare professional. Full Disclaimer  ·  Last Reviewed: July 2026  ·  Data Methodology