Partial vs Whole Breast Irradiation for Early-Stage Breast Cancer

Recruiting at 51 trial locations

Overseen By Erin McGean

Age: 18+

Sex: Female

Trial Phase: Phase 3

Sponsor: Ontario Clinical Oncology Group (OCOG)

Must be taking: Endocrine therapy

Disqualifiers: Age <50, BRCA positive, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Pivotal Trial (Near Approval) This treatment is in the last trial phase before FDA approval

Prior Safety Data This treatment has passed at least one previous human trial

Compensation: Varies

Number of Visits: 12

Duration: 1 week

910 Participants Needed

Trial Summary

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

What data supports the effectiveness of the treatment Partial Breast Irradiation (PBI) for early-stage breast cancer?

Research shows that accelerated partial breast irradiation (APBI) can provide similar long-term outcomes to whole breast irradiation (WBI) for early-stage breast cancer, with the added benefit of a shorter treatment duration. Studies have found that APBI effectively targets the cancer site while minimizing unnecessary radiation exposure to the rest of the breast. ^{1 2 3 4 5}

Is partial breast irradiation safe for humans?

Research shows that both partial breast irradiation (PBI) and whole breast irradiation (WBI) are generally safe for treating early-stage breast cancer, with studies indicating similar long-term safety outcomes for both methods. ^{1 2 3 4 6}

How does the treatment of Partial Breast Irradiation (PBI) differ from Whole Breast Irradiation (WBI) for early-stage breast cancer?

Partial Breast Irradiation (PBI) targets only the area around the lumpectomy site, reducing treatment time compared to Whole Breast Irradiation (WBI), which involves irradiating the entire breast over several weeks. PBI offers similar outcomes to WBI but with a shorter treatment duration. ^{1 2 4 5 7}

What is the purpose of this trial?

The primary objective of this study is to determine in women with node negative BC ≤3cm in size, if PBI compared to WBI, both given once-a-day over 1 week following BCS, is non-inferior for LR and reduces adverse cosmesis. The primary outcomes are LR and patient-assessed cosmesis at 3 years post randomization.

Research Team

Timothy J. Whelan

Principal Investigator

Juravinski Cancer Centre and McMaster University

Eligibility Criteria

This trial is for women over 50 with node-negative breast cancer that's 3cm or smaller, treated by surgery with clear margins. They must not be pregnant, lactating, BRCA positive, have a tumor larger than 3cm, multiple primary tumors in different quadrants of the same breast, a history of other cancers within the last five years (except certain skin cancers), or previous/synchronous contralateral breast cancer.

Inclusion Criteria

My underarm lymph nodes do not have cancer, confirmed by biopsy or surgery.

My breast cancer surgery removed all visible cancer with clear margins of at least 1mm.

I am a woman newly diagnosed with invasive breast cancer without spread.

Exclusion Criteria

I haven't had cancer other than non-melanoma skin cancer or in-situ carcinoma in the last 5 years.

My tumor bed cannot be seen on a CT scan.

Known pregnancy or currently lactating

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive either Partial Breast Irradiation (PBI) or Whole Breast Irradiation (WBI) with 26 Gy in 5 fractions over 5-7 days

1 week

5 visits (in-person)

Follow-up

Participants are monitored for local recurrence, cosmesis, quality of life, and other outcomes

5 years

Annually for 5 years

Radiation Toxicity Assessment

Assessment of acute and late radiation toxicity using NCI CTCAE version 5.0

3 months

2 weeks and 3 months post-radiation treatment

Treatment Details

Interventions

• Partial Breast Irradiation (PBI)
• Whole Breast Irradiation (WBI)

Trial Overview The study compares Partial Breast Irradiation (PBI) to Whole Breast Irradiation (WBI) in patients after breast-conserving surgery. Both treatments are given once daily over one week. The goal is to see if PBI is as effective as WBI at preventing local recurrence and maintaining good cosmetic results three years post-treatment.

Participant Groups

Group I: Partial Breast Irradiation (PBI) Experimental Treatment 1 Intervention

26 Gy in 5 fractions to the tumour bed with a margin of normal tissue

Group II: Whole Breast Irradiation (WBI) Active Control 1 Intervention

26 Gy in 5 fractions to the whole breast

Partial Breast Irradiation (PBI) is already approved in United States, European Union, Canada for the following indications:

Approved in United States as Partial Breast Irradiation for:

• Early-stage invasive breast cancer
• Ductal carcinoma in situ (DCIS)

Approved in European Union as Partial Breast Irradiation for:

• Early-stage invasive breast cancer
• Ductal carcinoma in situ (DCIS)

Approved in Canada as Partial Breast Irradiation for:

• Early-stage invasive breast cancer
• Ductal carcinoma in situ (DCIS)

Who Is Running the Clinical Trial?

Ontario Clinical Oncology Group (OCOG)

Lead Sponsor

Trials

65

Recruited

42,000+

GenesisCare AU

Collaborator

Trials

1

Recruited

910+

Findings from Research

In a study of 131 early-stage breast cancer patients, both accelerated partial breast irradiation (APBI) and whole breast irradiation (WBI) showed similar patient-reported outcomes in terms of quality of life, pain, and fatigue after treatment, indicating both methods are effective.

Patients receiving APBI reported less skin color change and breast elevation compared to those undergoing WBI, suggesting that APBI may have a cosmetic advantage in the short term.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Patient-reported outcomes of catheter-based accelerated partial breast brachytherapy and whole breast irradiation, a single institution experience. Jethwa, KR., Kahila, MM., Mara, KC., et al.[2022]

Accelerated partial breast irradiation (APBI) is being investigated as a potentially effective alternative to whole-breast irradiation (WBI) for patients undergoing breast-conservation therapy (BCT).

Current clinical trials are exploring various methods of APBI to determine its safety and efficacy compared to traditional WBI, indicating a shift in treatment approaches for breast cancer.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Integrating partial breast irradiation into surgical practice and clinical trials. Fearmonti, RM., Vicini, FA., Pawlik, TM., et al.[2007]

In a study of 290 patients receiving accelerated partial breast irradiation (APBI) with a median follow-up of 8 years, the rate of ipsilateral breast tumor recurrence (IBTR) was significantly higher (6.2%) compared to 1.0% in 290 patients receiving whole breast irradiation (WBI), indicating a greater risk of recurrence with APBI.

Despite the higher recurrence rates, APBI was associated with significantly fewer toxicities, such as fatigue and skin reactions, suggesting that while APBI may pose a higher risk of cancer recurrence, it offers a more tolerable treatment experience for patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A Single Institution Retrospective Comparison Study of Locoregional Recurrence After Accelerated Partial Breast Irradiation Using External Beam Fractionation Compared with Whole Breast Irradiation with 8 Years of Follow-Up. Shah, S., Kyrillos, A., Kuchta, K., et al.[2018]

In a study of 3009 patients treated with breast conserving therapy, both whole breast irradiation (WBI) and accelerated partial breast irradiation (APBI) showed similar long-term outcomes, with no significant differences in recurrence rates or survival after 10 years.

The analysis indicated that both treatment methods resulted in good to excellent cosmetic outcomes, with 94% of WBI patients and 95% of APBI patients reporting favorable results, suggesting that APBI can be a viable alternative to WBI without compromising effectiveness.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Brachytherapy-based Accelerated Partial Breast Irradiation Provides Equivalent 10-Year Outcomes to Whole Breast Irradiation: A Matched-Pair Analysis. Wobb, JL., Shah, C., Chen, PY., et al.[2017]

Accelerated partial breast irradiation (APBI) is a newer treatment option that focuses on irradiating only the lumpectomy site and surrounding margin, rather than the entire breast, which has been the traditional approach for 5-7 weeks after surgery.

The review discusses the evidence from modern clinical trials supporting APBI, highlighting its potential benefits and drawbacks, as well as ongoing debates about which patient groups may benefit most from this targeted treatment.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The evolving role of partial breast irradiation in early-stage breast cancer. Barry, M., Ho, A., Morrow, M.[2022]

Partial breast irradiation (PBI) is linked to a higher risk of local recurrence in early-stage breast cancer compared to whole breast irradiation (WBI), with an odds ratio of 1.69, indicating a significant concern for patients considering PBI.

Despite the increased local recurrence risk, PBI is associated with lower odds of death without breast cancer recurrence (OR 0.55), suggesting a potential survival benefit, particularly for women with smaller hormone receptor-positive tumors and no nodal involvement when treated with external beam radiation therapy (EBRT).

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Toxicity and clinical outcomes of partial breast irradiation compared to whole breast irradiation for early-stage breast cancer: a systematic review and meta-analysis. Korzets, Y., Fyles, A., Shepshelovich, D., et al.[2019]

Both accelerated partial-breast irradiation (APBI) techniques using 3D conformal radiation therapy (3DCRT) showed significantly improved conformity compared to conventional whole-breast irradiation (WBI) in a study involving 15 patients.

The APBI techniques maintained good dose homogeneity and did not significantly increase radiation exposure to surrounding organs at risk, indicating they are safe and effective alternatives for post-lumpectomy treatment.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dosimetric evaluation of 3Dconformal acceleratedpartial-breast irradiation vs. whole-breast irradiation: A comparative study. Kumar, R., Sharma, SC., Kapoor, R., et al.[2021]

References

1. Netherlands pubmed.ncbi.nlm.nih.gov

Patient-reported outcomes of catheter-based accelerated partial breast brachytherapy and whole breast irradiation, a single institution experience. [2022]

2. United States pubmed.ncbi.nlm.nih.gov

Integrating partial breast irradiation into surgical practice and clinical trials. [2007]

3. United States pubmed.ncbi.nlm.nih.gov

A Single Institution Retrospective Comparison Study of Locoregional Recurrence After Accelerated Partial Breast Irradiation Using External Beam Fractionation Compared with Whole Breast Irradiation with 8 Years of Follow-Up. [2018]

4. United States pubmed.ncbi.nlm.nih.gov

Brachytherapy-based Accelerated Partial Breast Irradiation Provides Equivalent 10-Year Outcomes to Whole Breast Irradiation: A Matched-Pair Analysis. [2017]

5. United States pubmed.ncbi.nlm.nih.gov

The evolving role of partial breast irradiation in early-stage breast cancer. [2022]

6. Netherlands pubmed.ncbi.nlm.nih.gov

Toxicity and clinical outcomes of partial breast irradiation compared to whole breast irradiation for early-stage breast cancer: a systematic review and meta-analysis. [2019]

7. India pubmed.ncbi.nlm.nih.gov

Dosimetric evaluation of 3Dconformal acceleratedpartial-breast irradiation vs. whole-breast irradiation: A comparative study. [2021]