An interventional study of Proton Radiation in Invasive Breast Cancer, sponsored by Massachusetts General Hospital. Completed at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-07-20.
Sponsored by Massachusetts General Hospital · Not applicable, Interventional, and Treatment
In this study we are looking at a type of radiation called proton radiation which is known to spare surrounding tissue and organs from radiation. The proton radiation will be delivered using 3D conformal proton radiation or scanned beam/IMPT (Intensity Modulated Proton Radiation Treatment). Proton radiation delivers no dose beyond the region requiring treatment. This may reduce side effects that patients would normally experience with conventional radiation therapy or other means of delivering proton radiation therapy. In this study we are evaluating the effectiveness of using proton radiation delivered to reduce side effects association with radiation treatment.
Proton radiation will be delivered daily for approximately 5 1/2 weeks. Patients will be assessed weekly for any side effects they may be experiencing.
Patients will have follow-up visits 4 weeks after proton therapy ends, at 6 months, 12 months, and then every year for up to five years after treatment. Follow-up visits will include a physical examination, radiological imaging (if necessary), echocardiogram, and laboratory tests.
12,544 studies on the registry are indexed under Breast Neoplasms; 2,892 are open to participants now.
This study's enrollment of 70 is close to the median of 72 across 9,303 interventional studies indexed under Breast Neoplasms.
Browse Breast Neoplasms studies →Massachusetts General Hospital is the lead sponsor of 2,536 studies on the registry; 446 are open to participants now.
Of its 214 completed or terminated interventional studies of FDA-regulated products, 161 (75%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Radiation therapy with proton beam
Radiation: Proton Radiation
45-50.4 Gy(RBE) to the chest wall and 45-50.5 Gy(RBE) once daily, 5 days per week, for approximately 5 1/2 weeks
Number of Participants With Grade 3 or Higher Radiation Pneumonitis or Any Grade 4 Adverse Event
To determine the feasibility of using proton radiation for the treatment of invasive breast cancer following mastectomy based on the occurrence of grade 3 or \> radiation pneumonitis or any grade 4 adverse event within 3 months after the completion of radiation treatment.
Time frame: From the start of treatment until 3 months after the end of treatment, median duration of treatment of 6 weeks
The Number of Participants With Acute Skin Toxicities
Summary of the number of participants with any grade acute skin toxicities. Acute skin toxicity was assessed from the start of treatment until 90 days after the end of treatment. Skin toxicity was assessed using Common Terminology Criteria for Adverse Events (CTCAE 4).
Time frame: From the start of treatment until 3 months after the end of treatment
Rate and Severity of Radiation Pneumonitis
The number of participants that experienced radiation pneumonitis within three months of the end of treatment. The participants that experienced radiation pneumonitis are grouped by grade. Adverse events were assessed using Common Terminology Criteria for Adverse Events (CTCAE 4). * Grade 1: Mild * Grade 2: Moderate * Grade 3: Severe * Grade 4: Life-Threatening * Grade 5: Fatal
Time frame: From the start of treatment until 3 months after the end of treatment and was not included in the analysis population.
Summary of Late Skin Toxicity
A summary of the late skin toxicities experienced by participants. The number of participants effected is shown for each toxicity experienced. Skin toxicities were assessed using Common Terminology Criteria for Adverse Events (CTCAE 4).
Time frame: From 3 months after the end of treatment up to 5 years
To Evaluate Cosmetic Outcome and Patient Satisfaction With Cosmetic Outcome
To evaluate cosmetic outcome and patient satisfaction with cosmetic outcome, see Secondary Outcome #7 for cosmetic outcomes.
Time frame: From the start of treatment until 5 years post treatment
Acute and Late Toxicity of Breast Reconstruction Following Proton Radiation
Combined summary of the acute (within 3 months of completing treatment) and late (3 months to 5 years after completion of treatment) toxicities experienced by participants thought to be related to breast reconstruction surgery following proton radiation treatment. Toxicities are assessed using Common Terminology Criteria for Adverse Events (CTCAE 4).
Time frame: From the start of treatment until 5 years post treatment
The Number of Participants That Needed Unplanned Additional Surgery for Breast Reconstruction
The number of participants that needed unplanned additional surgery for breast reconstruction post-RT.
Time frame: From the start of treatment until 5 years post treatment
The Number of Participants With Early Signs of Cardiac Effects From Radiation Therapy
The number of participant that had early signs of cardiac effects from radiation therapy as assessed using a Strain Echo-cardiogram. The data from the Echo-cardiogram was evaluated for signs of negative impacts to cardiac function as determined by the treating physician. Parameters considered in the evaluation of the echo-cardiogram by the physician included myocardial velocity, strain, strain rate, and torsion. Blood-based cardiac bio-markers pro-BNP and ultra-sensitive troponin-I were also assessed. Either a clinically meaningful change in the strain echo-cardiogram parameters or clinically meaningful elevation of the bio-markers was sufficient to be considered to have early signs of cardiac effects.
Time frame: Baseline and then 4 and 8 weeks post treatment
Progression Free Survival
Progression-free survival is defined as the duration from the start of radiation to the date of objective disease progression or death due to any cause, whichever is earlier. Disease progression is defined as the appearance of one or more new lesions.
Time frame: from the start of treatment until the time of disease progression, up to 5 years
| Milestone | Proton Radiation |
|---|---|
| Started | 70 |
| Completed | 69 |
| Not completed | 1 |
| Withdrew: Withdrawal by subject | 1 |
To determine the feasibility of using proton radiation for the treatment of invasive breast cancer following mastectomy based on the occurrence of grade 3 or \> radiation pneumonitis or any grade 4 adverse event within 3 months after the completion of radiation treatment.
| Participants | Proton Radiation |
|---|---|
| Number of Participants With Grade 3 or Higher Radiation Pneumonitis or Any Grade 4 Adverse Event | 0 |
Summary of the number of participants with any grade acute skin toxicities. Acute skin toxicity was assessed from the start of treatment until 90 days after the end of treatment. Skin toxicity was assessed using Common Terminology Criteria for Adverse Events (CTCAE 4).
| Participants | Proton Radiation |
|---|---|
| The Number of Participants With Acute Skin Toxicities | 69 |
The number of participants that experienced radiation pneumonitis within three months of the end of treatment. The participants that experienced radiation pneumonitis are grouped by grade. Adverse events were assessed using Common Terminology Criteria for Adverse Events (CTCAE 4). * Grade 1: Mild * Grade 2: Moderate * Grade 3: Severe * Grade 4: Life-Threatening * Grade 5: Fatal
| Participants | Proton Radiation |
|---|---|
| Grade 1 | 0 |
| Grade 2 | 0 |
| Grade 3 | 0 |
| Grade 4 | 0 |
| Grade 5 | 0 |
A summary of the late skin toxicities experienced by participants. The number of participants effected is shown for each toxicity experienced. Skin toxicities were assessed using Common Terminology Criteria for Adverse Events (CTCAE 4).
| Participants | Proton Radiation |
|---|---|
| Hyperpigmentation — Grade 1 | 36 |
| Hyperpigmentation — Grade 2 | 0 |
| Hyperpigmentation — Grade 3 | 0 |
| Hyperpigmentation — No late skin Toxicity | 33 |
| Telangiectasia — Grade 1 | 11 |
| Telangiectasia — Grade 2 | 0 |
| Telangiectasia — Grade 3 | 0 |
| Telangiectasia — No late skin Toxicity | 58 |
| Atrophy — Grade 1 | 1 |
| Atrophy — Grade 2 | 0 |
| Atrophy — Grade 3 | 0 |
| Atrophy — No late skin Toxicity | 68 |
| Lymphedema — Grade 1 | 1 |
| Lymphedema — Grade 2 | 0 |
| Lymphedema — Grade 3 | 0 |
| Lymphedema — No late skin Toxicity | 68 |
| Seroma — Grade 1 | 0 |
| Seroma — Grade 2 | 0 |
| Seroma — Grade 3 | 1 |
| Seroma — No late skin Toxicity | 68 |
| Infection — Grade 1 | 0 |
| Infection — Grade 2 | 0 |
| Infection — Grade 3 | 1 |
| Infection — No late skin Toxicity | 68 |
To evaluate cosmetic outcome and patient satisfaction with cosmetic outcome, see Secondary Outcome #7 for cosmetic outcomes.
| Participants | Proton Radiation |
|---|---|
| To Evaluate Cosmetic Outcome and Patient Satisfaction With Cosmetic Outcome | 0 |
Combined summary of the acute (within 3 months of completing treatment) and late (3 months to 5 years after completion of treatment) toxicities experienced by participants thought to be related to breast reconstruction surgery following proton radiation treatment. Toxicities are assessed using Common Terminology Criteria for Adverse Events (CTCAE 4).
| Participants | Proton Radiation |
|---|---|
| Skin Dermatitis — Grade 1 | 10 |
| Skin Dermatitis — Grade 2 | 57 |
| Skin Dermatitis — Grade 3 | 2 |
| Skin Dermatitis — No toxicity | 0 |
| Hyperpigmentation — Grade 1 | 36 |
| Hyperpigmentation — Grade 2 | 0 |
| Hyperpigmentation — Grade 3 | 0 |
| Hyperpigmentation — No toxicity | 33 |
| Telangiectasia — Grade 1 | 11 |
| Telangiectasia — Grade 2 | 0 |
| Telangiectasia — Grade 3 | 0 |
| Telangiectasia — No toxicity | 58 |
| Atrophy — Grade 1 | 1 |
| Atrophy — Grade 2 | 0 |
| Atrophy — Grade 3 | 0 |
| Atrophy — No toxicity | 68 |
| Lymphedema — Grade 1 | 1 |
| Lymphedema — Grade 2 | 0 |
| Lymphedema — Grade 3 | 0 |
| Lymphedema — No toxicity | 68 |
| Seroma — Grade 1 | 0 |
| Seroma — Grade 2 | 0 |
| Seroma — Grade 3 | 1 |
| Seroma — No toxicity | 68 |
| Infection — Grade 1 | 0 |
| Infection — Grade 2 | 0 |
| Infection — Grade 3 | 1 |
| Infection — No toxicity | 68 |
The number of participants that needed unplanned additional surgery for breast reconstruction post-RT.
| Participants | Proton Radiation |
|---|---|
| Single-stage impant | 9 |
| Tissue Expander to Implant | 3 |
| No pre-RT reconstruction | 1 |
The number of participant that had early signs of cardiac effects from radiation therapy as assessed using a Strain Echo-cardiogram. The data from the Echo-cardiogram was evaluated for signs of negative impacts to cardiac function as determined by the treating physician. Parameters considered in the evaluation of the echo-cardiogram by the physician included myocardial velocity, strain, strain rate, and torsion. Blood-based cardiac bio-markers pro-BNP and ultra-sensitive troponin-I were also assessed. Either a clinically meaningful change in the strain echo-cardiogram parameters or clinically meaningful elevation of the bio-markers was sufficient to be considered to have early signs of cardiac effects.
| Participants | Proton Radiation |
|---|---|
| The Number of Participants With Early Signs of Cardiac Effects From Radiation Therapy | 0 |
Progression-free survival is defined as the duration from the start of radiation to the date of objective disease progression or death due to any cause, whichever is earlier. Disease progression is defined as the appearance of one or more new lesions.
| Participants | Proton Radiation |
|---|---|
| Progression Free Survival | 59 |
Collected over Weekly during radiation treatment; 1, 2, 6, and 12 months post treatment; then yearly up until 5 years after the end of treatment (median duration of follow-up of about 36 months of follow-up at the time of analysis).. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Proton Radiation | 0/70 (0%) | 20/70 (28.6%) | 70/70 (100%) |
| Event | Proton Radiation |
|---|---|
| Surgical and medical procedures - Other, specifySurgical and medical procedures | 13/70 |
| Musculoskeletal and connective tissue disorders - Other, specifyMusculoskeletal and connective tissue disorders | 7/70 |
| Dermatitis radiationInjury, poisoning and procedural complications | 2/70 |
| Fibrosis deep connective tissueMusculoskeletal and connective tissue disorders | 1/70 |
| SeromaInjury, poisoning and procedural complications | 1/70 |
| Skin infectionInfections and infestations | 1/70 |
| Event | Proton Radiation |
|---|---|
| Dermatitis radiationInjury, poisoning and procedural complications | 69/70 |
| FatigueGeneral Disorders | 67/70 |
| Skin hyperpigmentationSkin and subcutaneous tissue disorders | 61/70 |
| Musculoskeletal and connective tissue disorder - OtherMusculoskeletal and connective tissue disorders | 48/70 |
| Chest wall painMusculoskeletal and connective tissue disorders | 42/70 |
| Fibrosis deep connective tissueMusculoskeletal and connective tissue disorders | 39/70 |
| PruritusSkin and subcutaneous tissue disorders | 39/70 |
| ArthralgiaMusculoskeletal and connective tissue disorders | 38/70 |
| Hot flashesVascular disorders | 37/70 |
| Joint range of motion decreasedMusculoskeletal and connective tissue disorders | 33/70 |
| Age, Continuous(years) | Proton Radiation |
|---|---|
| Median | 45 (25 to 70) |
| Sex: Female, Male(Participants) | Proton Radiation |
|---|---|
| Female | 70 |
| Male | 0 |
| Ethnicity (NIH/OMB)(Participants) | Proton Radiation |
|---|---|
| Hispanic or Latino | 0 |
| Not Hispanic or Latino | 63 |
| Unknown or Not Reported | 7 |
| Race (NIH/OMB)(Participants) | Proton Radiation |
|---|---|
| American Indian or Alaska Native | 0 |
| Asian | 6 |
| Native Hawaiian or Other Pacific Islander | 0 |
| Black or African American | 0 |
| White | 63 |
| More than one race | 0 |
| Unknown or Not Reported | 1 |
| Region of Enrollment(Participants) | Proton Radiation |
|---|---|
| United States | 70 |
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Massachusetts General Hospital