Neoplasms

Skin and Connective Tissue Diseases

All Conditions

Symptoms and General Pathology

Breast Neoplasms

Recurrence

Breast Diseases

Skin Diseases

Disease Attributes

BCS postulated to be at low risk for IBTR following Endocrine Therapy

Tim Whelan, MD

Sally Smith, MD

This is a multicentre, single-arm prospective cohort study evaluating risk of ipsilateral breast tumour recurrence(IBTR) following breast conserving surgery (BCS) in a group of women postulated to be at low risk for recurrence. Women with luminal A breast cancer determined by immunohistochemical(IHC) and other low risk clinical testing (see below) will be treated with endocrine therapy (tamoxifen or aromatase inhibitor) for five years and will not be treated with breast irradiation (BI). Subjects will be followed for 10 years and will be assessed for recurrent disease, new primary cancer and survival.

The independent prognostic ability of the luminal A subtype has been demonstrated in two retrospective analyses of prospective trials and suggests that luminal A combined with other known clinical prognostic factors could be used to select patients treated with BCS at very low risk for IBTR who could avoid BI. Given that using intrinsic subtyping combined with other clinical factors to identify women who could avoid BI would be a major change in clinical practice, we propose that a prospective study is necessary to confirm that such an approach can accurately identify a group of women at very low risk for IBTR following BCS.

We anticipate that the risk of IBTR in the low risk group is likely to be lower than that observed in previous trials (predicted to be \< 5% at 5 years and \< 10% at 10 years) for several reasons: first, our selection criteria (node negative, luminal A, \> or = 55 years, tumours \< or = 2cm, excision margin \> or = 1mm post-BCS, absence of lobular cancers, extensive intraductal component and lymphovascular invasion) are more restrictive than in previous trials and second, the risks of IBTR are steadily decreasing over time due to improvements in mammographic screening, pre-op staging, tumour localization, and surgical practice. The expected low failure rates are unlikely to warrant the use of radiation.

A prospective cohort study was identified as the most appropriate and efficient design as our primary hypothesis is that a group of patients at very low risk of IBTR can be identified. A randomized trial could address the effectiveness of radiation in such a cohort of patients, but would require a much larger sample size to detect very small differences, which would not be clinically meaningful. During the conduct of this trial it is anticipated that patients who do not meet study criteria or who decline study enrollment, will continue to receive BI after BCS.

Specimens will be used to determine Ki67 status by IHC and subsequent testing for DNA/RNA.

A Prospective Cohort Study Evaluating Risk of Local Recurrence Following Breast Conserving Surgery and Endocrine Therapy in Low Risk Luminal A Breast Cancer

The primary outcome is IBTR defined as recurrent invasive or in-situ cancer in the ipsilateral breast during follow-up. Histological evidence of recurrence will be required. All recurrences will be reviewed by a central adjudication committee.

Recurrence free interval (RFI) defined as time from registration to time of documented recurrent disease (ipsilateral breast, regional or distant)

Event-free survival (EFS) defined as the time from registration to the time of documented IBTR, regional (ipsilateral axilla, supraclavicular or internal mammary nodes), distant recurrence (bone, liver, lung, brain, etc.), contralateral breast cancer, new primary cancer or death

Overall survival (OS) defined as time from registration to death of any cause

British Columbia Cancer Agency

Ontario Clinical Oncology Group (OCOG)

Pathologic Complete Response

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).

Adrianne Van Dam

Sharon Nason

Meaghan Preston

Elena Parvez, Dr.

Carolyn Lim

Irene Karam, Dr

Gladys El-Helou

Olga Prescornic

Thierry Muanza, Dr

Mark Baski, Dr

Josee Allard

Valerie Theberge, Dr

Marie-Eve Caron

Julie Samson

Rafika Dahmane, Dr

Elena Parvez, MD

Thierry Muanza, MD

Mark Basik, MD

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

The study is a prospective, multi-center, single arm cohort study of omission of adjuvant whole breast radiation therapy (WBRT) following breast conserving surgery (BCS) in patients with a pathological complete response (pCR) following neoadjuvant chemotherapy (NAC). Eligible and consenting female patients with newly diagnosed T1-3 node negative breast cancer with no clinical evidence of distant metastatic disease, who have been treated with NAC, BCS and axillary staging surgery with final pathology demonstrating a pCR (ypT0N0) will be enrolled to the study and followed. The first analysis is planned when follow-up is a median of 5 years. Study participants will not receive adjuvant WBRT, the current standard of care.

The primary outcome is ipsilateral breast tumour recurrence (IBTR) at median 5-year follow-up. Study participants will be followed and assessed for local recurrence, regional recurrence, distant recurrence, DFS and OS. In addition, any additional breast cancer treatments received by the participant for the first recurrence event including repeat BCS, mastectomy, additional systemic therapy and radiation therapy (RT) will be documented. The planned sample size is 352 study participants.

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

Radiation OmisSion in PAtients With CLinically Node Negative Breast Cancer Undergoing Lumpectomy and With a PathologIc Complete REsponse After Neoadjuvant Chemotherapy

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.

defined as time from registration to undergoing ipsilateral mastectomy.

defined as time from registration to recurrence of invasive disease in the ipsilateral breast, regional nodes (axilla, supraclavicular, or internal mammary), distant areas beyond local or regional limits (distant recurrence), and death from breast cancer.

defined as time from registration to in breast invasive tumour recurrence, regional invasive recurrence, distant recurrence, contralateral breast cancer, second primary non-breast cancers, death from breast cancer, and death from non-breast cancer.

defined as time from registration to death from any cause.

Study title	NCT ID	Conditions	Eligibility	Organization
A Prospective Cohort Study Evaluating Risk of Local Recurrence Following Breast Conserving Surgery and Endocrine Therapy in Low Risk Luminal A Breast Cancer	NCT01791829	Breast Cancer	55 Years -	Ontario Clinical Oncology Group (OCOG)
A Prospective Cohort Study Evaluating Risk of Local Recurrence Following Breast Conserving Surgery and Endocrine Therapy in Low Risk Luminal A Breast Cancer	NCT01791829	Breast Cancer	55 Years -	Ontario Clinical Oncology Group (OCOG)
Radiation OmisSion in PAtients With CLinically Node Negative Breast Cancer Undergoing Lumpectomy	NCT05866458	Breast Cancer	50 Years -	Ontario Clinical Oncology Group (OCOG)
Radiation OmisSion in PAtients With CLinically Node Negative Breast Cancer Undergoing Lumpectomy	NCT05866458	Breast Cancer	50 Years -	Ontario Clinical Oncology Group (OCOG)

Spots Global Cancer Trial Database for ipsilateral breast tumour recurrence