Breast CancerPhase 2OPARNCT02637024
Trial of Radiation Fractionation Schedules for Once-a-Day Accelerated Partial Breast Irradiation
A Phase 2 study testing APBI: 30 Gy and APBI: 27.5 Gy in people with Breast Cancer and DCIS, run by Ontario Clinical Oncology Group (OCOG) at 10 sites in Canada.
Trial summary
This is a multi-centre randomized phase II trial in women with invasive carcinoma of the breast with negative axillary nodes or Ductal Carcinoma In-situ (DCIS) treated by Breast Conserving Surgery (BCS). Read more about this study
- Who is it for?
- Ages 50 years and older, women only
- Conditions the study is for
- Breast Cancer, DCIS
- What is being tested?
- APBI: 30 Gy and APBI: 27.5 Gy
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 280 participants
- Where
- 10 sitesCanada
- Study dates
- May 2016to Dec 2022
- Phase
- Phase 2
- Are there results?
- None posted in the registry
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 50 years and older
- Women only
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Females with a new histological diagnosis of DCIS or invasive carcinoma of the breast with no evidence of metastatic disease.
- Treated by BCS with microscopically clear resection margins for invasive and non-invasive disease (or no residual disease on re-excision).
- Negative axillary node involvement, including positive cells only identified by Immunohistochemistry (IHC) as determined either by sentinel node biopsy or axillary node dissection, or a clinical exam for patients with DCIS only.
Who cannot join
- Age less than 50 years
- Known to be Breast Cancer Type 1 Susceptibility Protein (BRCA 1) and/or Breast Cancer Type 2 Susceptibility Protein (BRCA 2) positive
- Tumour size >3 cm in greatest diameter on pathological examination (including the invasive and non-invasive components)
- Tumour invades the skin (i.e. T4 disease)
- Tumour histology limited to lobular carcinoma only
- Grade III invasive breast carcinoma or nuclear grade III for patients with DCIS alone
Show all 25Show fewer
- Triple negative invasive breast cancer
- Her2+ve invasive breast cancer that will not receive Herceptin
- Bilateral invasive malignancy of the breast (synchronous or metachronous)
- More than one primary tumor in different quadrants of the same breast
- Presence of an ipsilateral breast implant or pacemaker
- Status for adjuvant systemic therapy not determined
- Unable to commence radiation therapy:
- within 12 weeks of the last surgical procedure on the breast, or
- within 8 weeks of the last dose of chemotherapy
- Previous or concurrent malignancies except:
- Non-melanoma skin cancer
- Carcinoma in-situ of the cervix
- Invasive carcinoma of the cervix, endometrium, colon and thyroid, treated 5 years prior to study entry with no evidence of disease
- Serious non-malignant disease (e.g. cardiovascular, pulmonary, systemic lupus erythematosus (SLE), scleroderma) which would preclude definitive radiation treatment.
- Current pregnancy or lactating.
- Psychiatric or addictive disorders which would preclude obtaining informed consent or adherence to the protocol.
- Geographic inaccessibility for follow-up.
- Inability to localize surgical cavity on CT (i.e. no evidence of surgical clips or seroma)
- Inability to adequately plan the patient for the experimental technique.
Trial locations and contacts
10 sites in 1 country.
10 sites in 1 country
Canada10 sites
Simcoe Muskoka Regional Cancer Centre, Royal Victoria Hospital
Barrie, Ontario, L4M 6M2
Juravinski Cancer Centre
Hamilton, Ontario, L8V5C2
Grand River Regional Cancer Centre
Kitchener, Ontario, N2G 1G3
London Regional Cancer Program; London Health Sciences Centre
London, Ontario, N6A4L6
Hopital Maisonneuve-Rosemont
Montreal, Quebec, H1T 2M4
CHUM Centre Hospitalier de L'Université de Montréal
Montreal, Quebec, H2L 4M1
CHUQ Pavillon Hotel-Dieu Quebec
Québec, Quebec, G1R 2J6
CHUS - Hopital Fleurimont
Sherbrooke, Quebec, J1H 5N4
Odette Cancer Centre, Sunnybrook Health Sciences Centre
Toronto, Ontario, M4N 3M5
Windsor Regional Cancer Centre
Windsor, Ontario, N8W 2X3
About this study
Official title: A Phase II Randomized Trial of Radiation Fractionation Schedules for Once-a-Day Accelerated Partial Breast Irradiation (OPAR)
This is a multi-centre randomized phase II trial in women with invasive carcinoma of the breast with negative axillary nodes or Ductal Carcinoma In-situ (DCIS) treated by Breast Conserving Surgery (BCS). Eligible, consenting patients will be randomly allocated to receive radiotherapy of 3 Dimensional Conformal Radiation Therapy (3DCRT) Accelerated Partial Breast Irradiation (APBI) 30 Gray (Gy) in 5 daily fractions of 6Gy or 27.5Gy in 5 daily fractions of 5.5Gy over one week. Patients will be followed at 12, 24, 36 and 60 months post randomization. Cosmetic outcome will be measured using photographs and evaluated by a panel of trained radiation oncologists. Radiation toxicity will be assessed using National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE).
Read the detailed description
Women with invasive carcinoma of the breast with negative axillary nodes or DCIS, following BCS and/or chemotherapy, who meet the inclusion criteria will be screened and approached for eligibility assessment and potential study enrollment. All potentially eligible and consenting patients who do not meet the exclusion criteria will have a Computed Tomography (CT) simulation of the ipsilateral breast prior to randomization. All cases will be required to be planned prior to the randomization to ensure that dosimetric coverage and normal tissue restrictions can be met. If the seroma is not clearly visible or if the surgical clips do not adequately identify a previous surgical cavity, the patient will not be eligible for randomization.
Eligible, consenting patients will be randomly allocated to receive radiotherapy of 3DCRT APBI 30Gy in 5 daily fractions of 6Gy or 27.5Gy in 5 daily fractions of 5.5Gy over one week. Patients will be followed at 12, 24, 36 and 60 months post randomization. Cosmetic outcome will be measured using photographs and evaluated by a panel of trained radiation oncologists using the EORTC Breast Cosmetic Rating System. Radiation toxicity will be assessed using the NCI CTCAE version 4.02. The primary outcome is adverse cosmetic outcome at 2 years. The trial will be conducted in clinical centres within Canada.
- Conditions
- Breast Cancer, DCIS
- Being tested
- APBI: 30 Gy, APBI: 27.5 Gy
- Keywords
- Breast Cancer, DCIS, Radiotherapy, Partial breast irradiation, Radiation fractions
- Medical subject headings
- Breast Neoplasms, Carcinoma, Intraductal, Noninfiltrating
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
APBI: 30 GyRadiation
30 Gy in 5 fractions of 6 Gy, delivered daily, Monday to Friday, over a period of 5-8 days. A multiple small field 3D-conformal or intensity modulated radiation therapy (IMRT) technique will be used.
APBI: 27.5 GyRadiation
27.5 Gy in 5 fractions of 5.5 Gy, delivered daily, Monday to Friday, over a period of 5-8 days. A multiple small field 3D-conformal or intensity modulated radiation therapy (IMRT) technique will be used.
| Study group | Role | What they receive |
|---|---|---|
| APBI: 30 Gy | Experimental | Radiotherapy of 3 Dimensional Conformal Radiation Therapy (3DCRT) Accelerated Partial Breast Irradiation (APBI) 30 Gy in 5 daily fractions of 6 Gy Receives: Radiation: APBI: 30 Gy |
| APBI: 27.5 Gy | Experimental | Radiotherapy of 3 Dimensional Conformal Radiation Therapy (3DCRT) Accelerated Partial Breast Irradiation (APBI) 27.5 Gy in 5 daily fractions of 5.5 Gy Receives: Radiation: APBI: 27.5 Gy |
What is being measured
The primary outcome is the main question the study is designed to answer.
Adverse cosmetic outcome using the EORTC Breast Cosmetic Rating System
The primary outcome is adverse cosmesis assessed at 2 years post randomization as determined by photographic assessment. The cosmetic outcome will be assessed by a panel of 3 trained radiation oncologists who are unaware of treatment allocation, using the EORTC Breast Cosmetic Rating System for cosmetic results for breast conserving treatment. The treated breast is compared with the untreated breast for size, shape, location of the areola/nipple, appearance of the surgical scar, presence of telangiectasia, and a global cosmetic score based on these factors. Characteristics are graded on a 4-point scale: 0 = excellent; 1 = good; 2 = fair; 3 = poor. A global cosmetic score of fair or poor will be used as the primary outcome of adverse cosmesis.
Measured: 2 years post randomization
Secondary outcomes (5)
Cosmetic deterioration (defined as any adverse change in the global cosmetic score)
defined as any adverse change in the global cosmetic score from baseline to 2 years. Subjects with global cosmetic scores that were stable or improved from baseline to 2 years will be scored as 'no deterioration'.
Measured: Baseline to two years
Radiation toxicity assessed using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) v.4.02
defined as breast induration/fibrosis, shrinkage, and telangiectasia, which will be assessed using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) v.4.02.
Measured: 12, 24, 36 and 60 months
Ipsilateral breast tumour recurrence (IBTR)
defined as recurrent invasive or in situ cancer in the ipsilateral breast including the axillary tail. Histological evidence of local recurrence will be required.
Measured: Ongoing throughout study up to 5 years
Disease free survival (DFS)
defined as the time from randomization to the time of documented recurrent disease in the ipsilateral breast or regional nodes (supraclavicular, axillary or internal mammary) or distant sites (e.g. bone, liver, lung or brain).
Measured: Ongoing throughout study up to 5 years
Overall survival (OS)
defined as the time from randomization to death from any cause.
Measured: From date of randomization until the date of death up to 5 years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted22 Dec 2015 (estimated)
- Study startMay 2016
- Primary completionDec 2021
- Study completionDec 2022
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Breast CancerStudies 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
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 280 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Ontario Clinical Oncology Group (OCOG)
- Sponsor type
- University, hospital or other
- Collaborators
- Canadian Breast Cancer Foundation
- Responsible party
- Sponsor
- Investigators
- Do-Hoon Kim, MD, Principal investigator, Juravinski Cancer Centre
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT02637024
- Sponsor's protocol ID
- OCOG-2015-OPAR
- Acronym
- OPAR
- Status last verified
- Aug 2023
- First submitted
- 16 Dec 2015
- Last updated
- 14 Aug 2023
- Results posted
- No
- Data monitoring committee
- Yes
- Individual data sharing
- No
Publications
Kim DH, Theberge V, Parpia S, Kong I, Provencher S, Yassa M, Perera F, Lavertu S, Rousseau P, Lee J, Karam I, Schneider K, Levine MN, Whelan TJ; OPAR Study Investigators. OPAR: A Randomized Trial of Partial Breast Irradiation in Five Fractions Once Daily for Early Breast Cancer. J Clin Oncol. 2025 Feb 10;43(5):505-512. doi: 10.1200/JCO.24.00600. Epub 2024 Oct 8.
PubMed 39378393
Study at a glance
From the registry record, last updated by the sponsor on 14 Aug 2023. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase II Randomized Trial of Radiation Fractionation Schedules for Once-a-Day Accelerated Partial Breast Irradiation (OPAR)
- ClinicalTrials.gov ID
- NCT02637024
- Acronym / sponsor ID
- OPAR / OCOG-2015-OPAR
- Conditions
- Breast Cancer, DCIS
- Keywords
- Breast Cancer, DCIS, Radiotherapy, Partial breast irradiation, Radiation fractions
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 280 participants (estimated)
- Lead sponsor
- Ontario Clinical Oncology Group (OCOG)University, hospital or other
- Collaborators
- Canadian Breast Cancer Foundation
- Study start
- May 2016 (actual)
- Primary completion
- Dec 2021 (actual)
- Study completion
- Dec 2022 (actual)
- First posted
- 22 Dec 2015 (estimated)
- 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.
This is a multi-centre randomized phase II trial in women with invasive carcinoma of the breast with negative axillary nodes or Ductal Carcinoma In-situ (DCIS) treated by Breast Conserving Surgery (BCS). Eligible, consenting patients will be randomly allocated to receive radiotherapy of 3 Dimensional Conformal Radiation Therapy (3DCRT) Accelerated Partial Breast Irradiation (APBI) 30 Gray (Gy) in 5 daily fractions of 6Gy or 27.5Gy in 5 daily fractions of 5.5Gy over one week. Patients will be followed at 12, 24, 36 and 60 months post randomization. Cosmetic outcome will be measured using photographs and evaluated by a panel of trained radiation oncologists. Radiation toxicity will be assessed using National Cancer Institute Common Terminology Criteria for Adverse Events (NCI-CTCAE).
Detailed description
Women with invasive carcinoma of the breast with negative axillary nodes or DCIS, following BCS and/or chemotherapy, who meet the inclusion criteria will be screened and approached for eligibility assessment and potential study enrollment. All potentially eligible and consenting patients who do not meet the exclusion criteria will have a Computed Tomography (CT) simulation of the ipsilateral breast prior to randomization. All cases will be required to be planned prior to the randomization to ensure that dosimetric coverage and normal tissue restrictions can be met. If the seroma is not clearly visible or if the surgical clips do not adequately identify a previous surgical cavity, the patient will not be eligible for randomization.
Eligible, consenting patients will be randomly allocated to receive radiotherapy of 3DCRT APBI 30Gy in 5 daily fractions of 6Gy or 27.5Gy in 5 daily fractions of 5.5Gy over one week. Patients will be followed at 12, 24, 36 and 60 months post randomization. Cosmetic outcome will be measured using photographs and evaluated by a panel of trained radiation oncologists using the EORTC Breast Cosmetic Rating System. Radiation toxicity will be assessed using the NCI CTCAE version 4.02. The primary outcome is adverse cosmetic outcome at 2 years. The trial will be conducted in clinical centres within Canada.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| APBI: 30 Gy | Experimental | Radiation: APBI: 30 GyRadiotherapy of 3 Dimensional Conformal Radiation Therapy (3DCRT) Accelerated Partial Breast Irradiation (APBI) 30 Gy in 5 daily fractions of 6 Gy |
| APBI: 27.5 Gy | Experimental | Radiation: APBI: 27.5 GyRadiotherapy of 3 Dimensional Conformal Radiation Therapy (3DCRT) Accelerated Partial Breast Irradiation (APBI) 27.5 Gy in 5 daily fractions of 5.5 Gy |
Who may qualify
- Ages
- 50 years and older
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- Females with a new histological diagnosis of DCIS or invasive carcinoma of the breast with no evidence of metastatic disease.
- Treated by BCS with microscopically clear resection margins for invasive and non-invasive disease (or no residual disease on re-excision).
- Negative axillary node involvement, including positive cells only identified by Immunohistochemistry (IHC) as determined either by sentinel node biopsy or axillary node dissection, or a clinical exam for patients with DCIS only.
Key exclusion criteria (25 listed)
- Age less than 50 years
- Known to be Breast Cancer Type 1 Susceptibility Protein (BRCA 1) and/or Breast Cancer Type 2 Susceptibility Protein (BRCA 2) positive
- Tumour size >3 cm in greatest diameter on pathological examination (including the invasive and non-invasive components)
- Tumour invades the skin (i.e. T4 disease)
- Tumour histology limited to lobular carcinoma only
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| APBI: 30 Gy30 Gy in 5 fractions of 6 Gy, delivered daily, Monday to Friday, over a period of 5-8 days. A multiple small field 3D-conformal or intensity modulated radiation therapy (IMRT) technique will be used. | Radiation | APBI: 30 Gy |
| APBI: 27.5 Gy27.5 Gy in 5 fractions of 5.5 Gy, delivered daily, Monday to Friday, over a period of 5-8 days. A multiple small field 3D-conformal or intensity modulated radiation therapy (IMRT) technique will be used. | Radiation | APBI: 27.5 Gy |
Primary outcome
Adverse cosmetic outcome using the EORTC Breast Cosmetic Rating System
Time frame: 2 years post randomization
The primary outcome is adverse cosmesis assessed at 2 years post randomization as determined by photographic assessment. The cosmetic outcome will be assessed by a panel of 3 trained radiation oncologists who are unaware of treatment allocation, using the EORTC Breast Cosmetic Rating System for cosmetic results for breast conserving treatment. The treated breast is compared with the untreated breast for size, shape, location of the areola/nipple, appearance of the surgical scar, presence of telangiectasia, and a global cosmetic score based on these factors. Characteristics are graded on a 4-point scale: 0 = excellent; 1 = good; 2 = fair; 3 = poor. A global cosmetic score of fair or poor will be used as the primary outcome of adverse cosmesis.
5 secondary outcomes
Cosmetic deterioration (defined as any adverse change in the global cosmetic score)
Time frame: Baseline to two years
Radiation toxicity assessed using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) v.4.02
Time frame: 12, 24, 36 and 60 months
Ipsilateral breast tumour recurrence (IBTR)
Time frame: Ongoing throughout study up to 5 years
Disease free survival (DFS)
Time frame: Ongoing throughout study up to 5 years
Overall survival (OS)
Time frame: From date of randomization until the date of death up to 5 years
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 14 Aug 2023.
- Derived from this study: PubMed 39378393Kim DH, Theberge V, Parpia S, Kong I, Provencher S, Yassa M, Perera F, Lavertu S, Rousseau P, Lee J, Karam I, Schneider K, Levine MN, Whelan TJ; OPAR Study Investigators. OPAR: A Randomized Trial of Partial Breast Irradiation in Five Fractions Once Daily for Early Breast Cancer. J Clin Oncol. 2025 Feb 10;43(5):505-512. doi: 10.1200/JCO.24.00600. Epub 2024 Oct 8.
- Individual participant dataSharing planned: No
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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.
Do-Hoon Kim, MD principal investigator
Juravinski Cancer Centre
10 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing APBI: 30 Gy and APBI: 27.5 Gy in people with Breast Cancer and DCIS, run by Ontario Clinical Oncology Group (OCOG) at 10 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 3 inclusion and 25 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: finished, as of the sponsor's last update on 14 Aug 2023. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 10 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.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
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?
Adverse cosmetic outcome using the EORTC Breast Cosmetic Rating System (time frame: 2 years post randomization). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT02637024, which also lists 1 linked publication.
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 14 Aug 2023.