DCISELISANCT04797299
Prospective Evaluation of Breast-Conserving Surgery Alone in Low-Risk Ductal Carcinoma in Situ (DCIS)
An observational study of DCIS, run by Ontario Clinical Oncology Group (OCOG) at 24 sites in Canada.
Trial summary
To evaluate whether the combination of clinicopathological factors and the use of the Oncotype DX DCIS score can avoid radiation in women with low risk DCIS who have had breast conserving surgery (BCS) Read more about this study
- Who is it for?
- Ages 46 years and older, women only
- Conditions the study is for
- DCIS
- How many people
- 526 participants
- Where
- 24 sitesCanada
- Study dates
- 23 Nov 2022to 30 Nov 2035
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 46 years and older
- Women only
- No healthy volunteers
- Adult, Older adult
Study population: Prospective cohort study conducted in Canada in women with a low risk DCIS following breast conserving surgery who are candidates for radiation. Eligibility status should be confirmed by the referring physician or delegate prior to enrollment. It is important that no exceptions are made to the eligibility criteria. Questions related to eligibility requirements and/or specific criteria should be addressed with OCOG prior to enrollment
Who may be able to join
- Female patient > 45 years of age with DCIS without microinvasion.
- Tumour size ≤ 2.5cm.
- Treated by BCS with clear resection margins ≥ 2 mm or no residual disease on re-excision.*
- Patients with anterior margins and posterior margins ≥1 mm are eligible. Or if the dissection was confirmed to be taken to skin and down to fascia with no DCIS present at inked margins.
- Oncotype DX DCIS score with a predicted 10-year risk of LR ≤10%.
Who cannot join
- Multifocal DCIS.
- History of any invasive breast cancer or non-invasive breast cancer in the ipsilateral breast.
- Synchronous or previous invasive or non-invasive breast cancer.
- Prior history of invasive cancer within the last 5 years, excluding non-melanoma skin cancers.
- ECOG performance status ≥3.
- Life expectancy <10 years.
- Geographic inaccessibility for follow-up.
Trial locations and contacts
24 sites in 1 country.
24 sites in 1 country
Canada24 sites
BC Cancer - Abbotsford Centre
Abbotsford British Columbia, British Columbia, V2S 0C2
Royal Victoria Regional Health Centre
Barrie, Ontario, L4M 6M2
Arthur J.E. Child Comprehensive Cancer Centre
Calgary, Alberta, T2N 5G2
Cross Cancer Institute
Edmonton, Alberta, T6G 1Z2
Hôpital Charles Le Moyne (CISSS de la Montérégie-Centre)
Greenfield Park, Quebec, J4V 2H1
QE II HSC - Nova Scotia Cancer Centre
Halifax, Nova Scotia, B3H 1V7
Juravinski Cancer Centre
Hamilton, Ontario, L8V 5C2
London Regional Cancer Program
London, Ontario, N6A 4L6
CHUM - Centre Hospitalier de L'Université de Montréal
Montreal, Quebec, H2L 4M1
McGill University Health Centre
Montreal, Quebec, H4A 3J1
BC Cancer - Centre for the North (Prince George)
Prince George, British Columbia, V2M 7E9
Centre intégré de cancérologie du CHU de Québec - Université Laval
Québec, Quebec, G1J 1Z4
Allan Blair Cancer Centre
Regina, Saskatchewan, S4T 7T1
Saskatoon Cancer Centre
Saskatoon, Saskatchewan, S7N4H4
BC Cancer - Fraser Valley Centre
Surrey, British Columbia, V3V 1Z2
Cape Breton Cancer Centre
Sydney, Nova Scotia, B1P 1P3
Regional Cancer Care, Thunder Bay Regional Health Sciences Centre
Thunder Bay, Ontario, P7B 6V4
Sunnybrook Health Science Centre -Odette Cancer Centre
Toronto, Ontario, M4N 3M5
University Health Network - Princess Margaret Cancer Centre
Toronto, Ontario, M5G 2M9
Centre Intégré Universitaire de Santé et de Services Sociaux de la Mauricie- Centre-du-Québec (CIUSSS MCQ) - Trois-Rivières
Trois-Rivières, Quebec, G8Z 3R9
BC Cancer - Vancouver Centre
Vancouver, British Columbia, V5Z 4E6
BC Cancer - Victoria
Victoria, British Columbia, V8R 6V5
Windsor Regional Cancer Centre
Windsor, Ontario, N8W 2X3
CancerCare Manitoba
Winnipeg, Manitoba, R3E 0V9
About this study
Official title: Prospective Evaluation of Breast-Conserving Surgery Alone in Low-Risk Ductal Carcinoma in Situ Defined by a Molecular Expression Assay Combined With Clinico-Pathological Features
To evaluate whether the combination of clinicopathological factors and the use of the Oncotype DX DCIS score can avoid radiation in women with low risk DCIS who have had breast conserving surgery (BCS)
Read the detailed description
A prospective cohort study, conducted in Canada, to prospectively evaluate whether the combination of clinicopathological criteria and the Oncotype DX DCIS score can identify a group of women at very low risk of local recurrence following breast conserving surgery who do not require breast radiation therapy. We plan to screen 809 consenting women who will have their tumour tissue specimen sent to Exact Sciences to assess their DCIS score. We anticipate that 526 women will have an Oncotype DX DCIS score with a predicted 10-year risk of local recurrence ≤10%, these women will be enrolled and followed as part of the study.
At each centre, all patients with DCIS referred to radiation oncology will be documented. When a physician identifies an eligible patient, the patient will be approached by the referring physician or delegate to voluntarily provide informed consent to participate in this study. Consenting patients will be registered through the Ontario Clinical Oncology Group's (OCOG) web-based registration system. A two-step registration/enrollment process will be implemented.
Data related to the patient demographics, surgery details, tumour characteristics and ECOG performance will be collected. The patient's tumour specimen will be sent for analysis to Exact Sciences. The DCIS score results will be sent to the referring physician. OCOG will also receive the DCIS score results. Patients will be followed yearly up to 10 years. Bilateral mammograms and breast exams will be performed annually. The study data will be verified by source documentation.
- Conditions
- DCIS
- Keywords
- Ductal Carcinoma in Situ, Breast Conserving Surgery, Oncotype DX DS
- Medical subject headings
- Carcinoma, Intraductal, Noninfiltrating
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Single Arm Cohort | Evaluating the risk of Local Recurrence (LR) in a group of women postulated to be at low risk of LR following Breast Conserving Surgery alone defined by a combination of clinicopathological factors and Oncotype DX DCIS score. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Ipsilateral local recurrence (LR)
Defined as recurrent invasive or in situ cancer in the ipsilateral breast
Measured: 5 Year
Secondary outcomes (5)
Ipsilateral invasive local recurrence
defined as time from study registration to time of recurrent invasive cancer in the ipsilateral breast
Measured: 5 Year
Breast cancer recurrence-free interval (RFI)
defined as time from study registration to time of documented recurrent disease (ipsilateral breast (DCIS or invasive), regional, distant or death from breast cancer
Measured: 5 Year
Distant disease-free survival (DDFS)
defined as time from study registration to distant recurrence
Measured: 5 Year
Disease-free survival (DFS)
defined as time from registration to time of LR (DCIS or invasive), regional and distant recurrence, contralateral breast cancer, new primary (non-breast) and death from any cause
Measured: 5 Year
Overall survival (OS)
defined as time from registration to death of any cause
Measured: 5 Year
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted15 Mar 2021
- Study start23 Nov 2022
- Primary completion30 Nov 2030 (estimated)
- Study completion30 Nov 2035 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for DCISStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 526 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Ontario Clinical Oncology Group (OCOG)
- Sponsor type
- University, hospital or other
- Collaborators
- Canadian Institutes of Health Research (CIHR), Hamilton Health Sciences Corporation
- Responsible party
- Sponsor
- Investigators
- Eileen Rakovitch, M.D., Principal investigator, Sunnybrook Research Institute, Sunnybrook Health ScienceTim Whelan, M.D, Principal investigator, Juravinski Cancer Centre
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04797299
- Sponsor's protocol ID
- OCOG-2021-ELISA
- Acronym
- ELISA
- Status last verified
- Jun 2026
- First submitted
- 10 Mar 2021
- Last updated
- 5 Oct 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 5 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Prospective Evaluation of Breast-Conserving Surgery Alone in Low-Risk Ductal Carcinoma in Situ Defined by a Molecular Expression Assay Combined With Clinico-Pathological Features
- ClinicalTrials.gov ID
- NCT04797299
- Acronym / sponsor ID
- ELISA / OCOG-2021-ELISA
- Conditions
- DCIS
- Keywords
- Ductal Carcinoma in Situ, Breast Conserving Surgery, Oncotype DX DS
- Study type
- Observational
- Recruitment status
- Active, not recruiting
- Enrolment
- 526 participants (estimated)
- Lead sponsor
- Ontario Clinical Oncology Group (OCOG)University, hospital or other
- Collaborators
- Canadian Institutes of Health Research (CIHR), Hamilton Health Sciences Corporation
- Study start
- 23 Nov 2022 (actual)
- Primary completion
- 30 Nov 2030 (estimated)
- Study completion
- 30 Nov 2035 (estimated)
- First posted
- 15 Mar 2021 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
To evaluate whether the combination of clinicopathological factors and the use of the Oncotype DX DCIS score can avoid radiation in women with low risk DCIS who have had breast conserving surgery (BCS)
Detailed description
A prospective cohort study, conducted in Canada, to prospectively evaluate whether the combination of clinicopathological criteria and the Oncotype DX DCIS score can identify a group of women at very low risk of local recurrence following breast conserving surgery who do not require breast radiation therapy. We plan to screen 809 consenting women who will have their tumour tissue specimen sent to Exact Sciences to assess their DCIS score. We anticipate that 526 women will have an Oncotype DX DCIS score with a predicted 10-year risk of local recurrence ≤10%, these women will be enrolled and followed as part of the study.
At each centre, all patients with DCIS referred to radiation oncology will be documented. When a physician identifies an eligible patient, the patient will be approached by the referring physician or delegate to voluntarily provide informed consent to participate in this study. Consenting patients will be registered through the Ontario Clinical Oncology Group's (OCOG) web-based registration system. A two-step registration/enrollment process will be implemented.
Data related to the patient demographics, surgery details, tumour characteristics and ECOG performance will be collected. The patient's tumour specimen will be sent for analysis to Exact Sciences. The DCIS score results will be sent to the referring physician. OCOG will also receive the DCIS score results. Patients will be followed yearly up to 10 years. Bilateral mammograms and breast exams will be performed annually. The study data will be verified by source documentation.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Single Arm Cohort | – | –Evaluating the risk of Local Recurrence (LR) in a group of women postulated to be at low risk of LR following Breast Conserving Surgery alone defined by a combination of clinicopathological factors and Oncotype DX DCIS score. |
Who may qualify
- Ages
- 46 years and older
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Prospective cohort study conducted in Canada in women with a low risk DCIS following breast conserving surgery who are candidates for radiation. Eligibility status should be confirmed by the referring physician or delegate prior to enrollment. It is important that no exceptions are made to the eligibility criteria. Questions related to eligibility requirements and/or specific criteria should be addressed with OCOG prior to enrollment
Key inclusion criteria (5 listed)
- Female patient > 45 years of age with DCIS without microinvasion.
- Tumour size ≤ 2.5cm.
- Treated by BCS with clear resection margins ≥ 2 mm or no residual disease on re-excision.*
- Oncotype DX DCIS score with a predicted 10-year risk of LR ≤10%.
Key exclusion criteria (7 listed)
- Multifocal DCIS.
- History of any invasive breast cancer or non-invasive breast cancer in the ipsilateral breast.
- Synchronous or previous invasive or non-invasive breast cancer.
- Prior history of invasive cancer within the last 5 years, excluding non-melanoma skin cancers.
- ECOG performance status ≥3.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Ipsilateral local recurrence (LR)
Time frame: 5 Year
Defined as recurrent invasive or in situ cancer in the ipsilateral breast
5 secondary outcomes
Ipsilateral invasive local recurrence
Time frame: 5 Year
Breast cancer recurrence-free interval (RFI)
Time frame: 5 Year
Distant disease-free survival (DDFS)
Time frame: 5 Year
Disease-free survival (DFS)
Time frame: 5 Year
Overall survival (OS)
Time frame: 5 Year
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 5 Oct 2026.
- TRACE/OCOG website accessed by clinical centresLink provided by the sponsor.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Eileen Rakovitch, M.D. principal investigator
Sunnybrook Research Institute, Sunnybrook Health Science
Tim Whelan, M.D principal investigator
Juravinski Cancer Centre
24 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of DCIS, run by Ontario Clinical Oncology Group (OCOG) at 24 sites in Canada.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 5 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 24 sites in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Ipsilateral local recurrence (LR) (time frame: 5 Year). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 5 Oct 2026.