Proton Therapy for Early Stage Breast Cancer

This study is looking at how proton radiation therapy works for women with early-stage breast cancer. Researchers want to see if this type of radiation, which focuses on just the tumor area, can be as effective as traditional radiation while causing fewer side effects. The main goal is to measure how many women remain free from the cancer returning in the treated breast after three years. You may be able to join if you are a woman, at least 50 years old, and have early-stage breast cancer. The study is currently enrolling 132 participants, but its current status is unclear.

Study design
This is an interventional study planning to enroll 132 women to assess the effects of proton radiation therapy.
What's involved
Not specified in the trial record.
Compensation
Not stated in the trial record.
Follow-up
The primary endpoint is measured at 3 years, suggesting participants will be followed for at least that long.

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NCT01766297

Phase II Protocol of Proton Therapy for Partial Breast Irradiation in Early Stage Breast Cancer

Recruiting
PHASE2Ages 50+InterventionalTreatment
Proton Collaborative Group
~132 participants
Updated 2025-09-09 on ClinicalTrials.gov
What's tested:Proton Radiotherapy

At a glance

Recruiting sites
9 of 9 listed sites are recruiting right now
RecruitingSuspended, closed, or not yet open
What they're measuring
To assess events of freedom from ipsilateral breast recurrence occurrences in patients receiving partial breast proton radiation therapy limited to the region of the tumor.
Measured over At 3 years
Breast Cancer
Breast Neoplasm
Breast Tumor
Cancer of the Breast
9 sites across 8 states
Virginia2
Arizona1
California1
Illinois1
Maryland1
Michigan1
New York1
Oklahoma1
  • Andrew Chang, MD · STUDY_CHAIR · Proton Collaborative Group

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Eligibility criteria

Inclusion

Must sign study-specific, IRB approved informed consent form prior to study entry. Note consent by legally authorized representative is not allowed for this trial.
Must be female.
Must be \> = 50 years of age.
Must have a life expectancy of at least 5 years based on age and co-morbidities.
Must have pathology proven invasive ductal carcinoma (lobular is not allowed) and/or ductal carcinoma in situ (DCIS).
One of the following criteria must be met: (a) Tumors that are microscopically multifocal must be 3.0 cm or less in total aggregate size and encompassed within a single scar (b) Patient does not have microscopically multifocal tumor.
For tumors that are invasive, if in the presence of extensive intraductal component (EIC), the entire pathologic tumor size (including both the intraductal and invasive component) must be 3.0 cm or less.
Must be Stage 0, I, II (Tis, T1, or T2, N0, M0 per AJCC criteria 7th and/or 8th Ed.). If stage II, the tumor size must be \< = 3.0 cm. A patient with invasive histology must have nodal stage pN0 by H\&E stains on sentinel node biopsy or axillary lymph node dissection.
Must have ER positive disease with ER/PR report available.
For tumors that are invasive, HER2 must be performed (positive or negative is acceptable).
Must have a lumpectomy performed, with documented negative surgical margins by 0.2 cm or more. If re-excision results in negative surgical margins 0.2 cm or more, patient is eligible.
If image guidance with daily cone beam CT with direct physician visual assessment is used for treatment positioning, the presence of markers or clips in the surgical bed is recommended but not required. If cone beam CT imaging will NOT be used for image guidance, then the patient must be prepared to have 2 fiducial markers minimum, 3 preferred, placed prior to treatment (if not previously done).
If markers or clips were placed at the time of surgery, patient must be able to start treatment within 12 weeks after lumpectomy or re-excision for adequate margins.
If markers were not placed at the time of surgery and are needed, patient must have markers placed within 6 weeks after surgery.
If systemic chemotherapy was given, patient must have had clips or markers placed at the time of surgery (if they are needed) and patient must have simulation scans within 6 weeks of the completion of the chemotherapy.
Must be able to start treatment within 12 weeks of surgery or 8 weeks of finalization of chemotherapy.

Exclusion

Previous history of ipsilateral invasive breast cancer or DCIS.
Any clinical or radiographically suspicious nodes, unless biopsy proven benign.
Non-epithelial malignancies such as sarcoma or lymphoma.
Suspicious residual microcalcifications on mammography of either breast, unless negative for malignancy on pathology.
Multicentric or bilateral disease unless biopsy of the clinical abnormalities are performed and result is negative.
Lymphovascular space invasion (LVSI) on pathology specimen.
Any previously treated breast carcinoma or synchronous breast carcinoma in ipsilateral breast.
Prior radiation therapy to the ipsilateral breast or thorax.
Paget's disease of the nipple.
Histologic examination showing invasive lobular histology.
Skin involvement.
Breasts technically unsatisfactory for radiation treatment upon the discretion of the treating physician.
Significant infection or other co-existing medical condition that would preclude protocol therapy such as pregnancy, HIV/AIDS or collagen vascular diseases specifically systemic lupus erythematosus, scleroderma, or dermatomyositis.
Known BRCA 1 or BRCA 2 mutation.
Pregnant or lactating.
  • To assess events of freedom from ipsilateral breast recurrence occurrences in patients receiving partial breast proton radiation therapy limited to the region of the tumor.At 3 years

    Freedom from failure (FFF): The events for FFF will be the first ipsilateral breast cancer recurrence. It is expected that less than 3% of patients will experience an ipsilateral breast cancer recurrence (FFF ≥ 97%). A recurrence rate of ≥ 10% (FFF ≤ 90%) is considered unacceptable. Therefore, the null hypothesis is the FFF of ipsilateral breast cancer recurrence is 90% or lower and the alternative hypothesis is that FFF of ipsilateral breast cancer is 97% or higher.