Proton Therapy for Breast Cancer

Overseen by Samantha Hedrick, PhD

Age: 18+

Sex: Female

Travel: May Be Covered

Time Reimbursement: Varies

Trial Phase: Academic

Recruiting

Sponsor: Thompson Cancer Survival Center

Disqualifiers: Stage IV cancer, Prior radiation, Pregnancy, others

No Placebo Group

Approved in 3 Jurisdictions

Trial Summary

What is the purpose of this trial?

This purpose of this study is to examine skin reactions (called radiation dermatitis) that occur during pencil beam scanning (PBS) proton therapy. The researchers will test a unique technique called "Spot Delete" to see if it can reduce skin reactions for breast patients treated with PBS. They will also use a special computer model to study how the energy of the proton beam (linear energy transfer) is related to these skin reactions. The study involves creating a treatment plan based on a CT scan, which helps guide the proton beam in the body. The clinical team uses this CT scan to find the best placement for the protons. The "Spot Delete" method prevents protons from stopping in the skin, which is thought to cause skin redness.

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 study team or your doctor.

What data supports the effectiveness of the treatment Pencil Beam Scanning Proton Therapy for breast cancer?

Research suggests that Pencil Beam Scanning Proton Therapy (PBS) may lower the risk of developing secondary cancers in breast cancer patients compared to traditional photon radiotherapy. This is because PBS can more precisely target the cancer, reducing radiation exposure to healthy tissues. ^{1 2 3 4 5}

Is pencil beam scanning proton therapy safe for humans?

Research shows that pencil beam scanning proton therapy is generally safe for humans, with studies indicating it reduces the risk of secondary cancers in breast cancer patients and has manageable acute toxicities in gynecologic cancer patients. ^{3 4 5 6 7}

How is Pencil Beam Scanning Proton Therapy different from other treatments for breast cancer?

Pencil Beam Scanning Proton Therapy (PBS) is unique because it uses a focused beam of protons to precisely target cancer cells, reducing radiation exposure to surrounding healthy tissues and potentially lowering the risk of secondary cancers compared to traditional photon-based therapies. ^{3 4 5 8 9}

Research Team

Samantha Hedrick, PhD

Principal Investigator

Director of Medical Physics

Eligibility Criteria

This trial is for adults with stage 0, I, II, or III breast cancer who've had a lumpectomy or mastectomy. They must not have prior radiation therapy to the chest, be pregnant/lactating, have certain collagen diseases like scleroderma or active dermatomyositis, Paget's disease of the nipple, Stage IV cancer, severe psychiatric conditions or other health issues that could interfere with treatment.

Inclusion Criteria

The patient must consent to be in the study and must have signed an approved consent form conforming to federal and institutional guidelines

Testing for progesterone receptors in my cancer is optional.

I don't have serious health issues that could affect my treatment.

Exclusion Criteria

I have Paget's disease of the nipple.

My breast cancer is at stage IV.

My breast cancer is not the common type but rather a rare form like sarcoma or lymphoma.

Trial Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive pencil beam scanning proton therapy with the 'Spot Delete' technique to reduce skin reactions

10 weeks

Weekly assessments

Follow-up

Participants are monitored for skin reactions and effectiveness of the 'Spot Delete' technique post-treatment

6 months

2 visits (1-month and 6-months post-treatment)

Treatment Details

Interventions

• Pencil Beam Scanning Proton Therapy (Proton Beam Therapy)

Trial Overview The study tests 'Spot Delete' in pencil beam scanning proton therapy for breast cancer patients to see if it reduces skin reactions. It involves using CT scans to guide proton beams and avoid them stopping in the skin which may cause redness.

Pencil Beam Scanning Proton Therapy is already approved in Japan for the following indications:

Approved in Japan as Pencil Beam Scanning Proton Therapy for:

• Breast cancer
• Brain tumors
• Spinal tumors
• Pediatric cancers
• Eye tumors
• Hepatocellular carcinoma

Who Is Running the Clinical Trial?

Thompson Cancer Survival Center

Lead Sponsor

Trials

4

Recruited

800+

Findings from Research

The study analyzed 10 lung cancer patients and found that the motion index (MI) can predict the level of dose degradation in proton pencil beam scanning (PBS) treatment, indicating that larger tumor motion leads to greater dose errors.

Using MI as a clinical decision tool can help determine if lung cancer patients with significant tumor motion are suitable candidates for PBS treatment, potentially improving treatment planning and outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A study of the beam-specific interplay effect in proton pencil beam scanning delivery in lung cancer. Kang, M., Huang, S., Solberg, TD., et al.[2022]

In a study of 304 men with localized prostate cancer, those treated with pencil beam scanning (PBS) showed a higher proportion of significant declines in urinary quality of life (QOL) compared to those treated with passive scatter/uniform scanning (PS/US) at 12 months, indicating a potential difference in outcomes between the two proton therapy methods.

However, overall average quality-of-life declines did not significantly differ between PBS and PS/US, suggesting that while there may be specific areas of concern, both treatment modalities have similar average effects on patient-reported outcomes over time.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Patient reported outcomes following proton pencil beam scanning vs. passive scatter/uniform scanning for localized prostate cancer: Secondary analysis of PCG 001-09. Mishra, MV., Khairnar, R., Bentzen, SM., et al.[2022]

In a study of 11 women with gynecologic cancers receiving pencil beam scanning (PBS) proton therapy, the treatment showed a low incidence of acute toxicities, with only 33% experiencing grade 2 hematologic toxicities and 9% experiencing grade 3 gastrointestinal toxicity, indicating a relatively safe profile.

PBS demonstrated significant dosimetric advantages over intensity-modulated radiation therapy (IMRT), particularly in sparing surrounding normal tissues like pelvic bone marrow, bladder, and small bowel from low doses, while maintaining robust target coverage despite setup uncertainties.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Initial Report of Pencil Beam Scanning Proton Therapy for Posthysterectomy Patients With Gynecologic Cancer. Lin, LL., Kirk, M., Scholey, J., et al.[2020]

Proton pencil beam scanning (PBS) therapy significantly reduces the risk of secondary cancers in breast cancer patients compared to traditional photon therapies, with a notable reduction in risk for younger patients with nodal involvement.

In a study involving 10 breast cancer patients, PBS showed a lower cumulative excess absolute risk for secondary cancers in the lungs and contralateral breast compared to tangential 3D-CRT and VMAT, highlighting its potential as a safer treatment option.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Proton pencil beam scanning reduces secondary cancer risk in breast cancer patients with internal mammary chain involvement compared to photon radiotherapy. Cartechini, G., Fracchiolla, F., Menegotti, L., et al.[2021]

In a study involving 11 patients with rectal cancer, preoperative short-course pencil beam scanning proton therapy (PBS-PT) effectively reduced radiation exposure to normal tissues compared to traditional photon therapies (3DCRT and VMAT).

PBS-PT provided similar coverage of the clinical target volume while significantly lowering the radiation dose to critical organs like the small and large bowel, bladder, and femoral heads, suggesting a safer treatment option for patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Clinical Implementation of Preoperative Short-Course Pencil Beam Scanning Proton Therapy for Patients With Rectal Cancer. Jeans, EB., Jethwa, KR., Harmsen, WS., et al.[2022]

In a study of 19 children with neuroblastoma treated with pencil beam scanning proton beam therapy (PBS-PT), the early outcomes were promising, showing a 2-year overall survival rate of 94% and no local recurrences during a median follow-up of 14.9 months.

The use of volumetric rescanning (vRSC) for motion mitigation was found to be safe and feasible, although its clinical relevance may be limited for children with minimal organ motion (<5 mm) during treatment.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Pencil Beam Scanning Proton Therapy for Paediatric Neuroblastoma with Motion Mitigation Strategy for Moving Target Volumes. Lim, PS., Pica, A., Hrbacek, J., et al.[2022]

A novel patient-specific quality assurance (psQA) program using a high-resolution 2D strip ionization chamber array (SICA) was developed and validated for ultra-high dose rate (UHDR) FLASH proton therapy, demonstrating excellent accuracy in measuring dose and dose rate.

The SICA-based QA framework achieved high gamma passing rates (96.6% for dose and 98.8% for dose rate) compared to treatment planning system predictions, indicating its effectiveness in ensuring the safety and efficacy of FLASH radiotherapy in clinical settings.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Implementation of novel measurement-based patient-specific QA for pencil beam scanning proton FLASH radiotherapy. Huang, S., Yang, Y., Wei, S., et al.[2023]

Proton Pencil Beam Scanning (PBS) can potentially deliver high FLASH dose rates (≥40 Gy/s) effectively, but this is limited to smaller fields (less than 4x4 cm²) and requires cyclotron output currents above 500 nA.

While achieving FLASH dose rates for larger fields is challenging, local FLASH delivery to specific areas of the treatment volume is feasible, suggesting that with further research, PBS techniques can be adapted for enhanced FLASH proton radiotherapy.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Current delivery limitations of proton PBS for FLASH. Zou, W., Diffenderfer, ES., Cengel, KA., et al.[2021]

Pencil-beam scanning (PBS) technology allows for precise targeting of bulky tumors, improving the dose delivered to the tumor while minimizing exposure to surrounding healthy tissue, as demonstrated in a case study of a large retroperitoneal sarcoma.

PBS simplifies treatment planning and delivery, reduces treatment time, and lowers costs compared to traditional proton therapy methods, making it a promising option for effective radiotherapy.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A case study in proton pencil-beam scanning delivery. Kooy, HM., Clasie, BM., Lu, HM., et al.[2018]

References

1. England pubmed.ncbi.nlm.nih.gov

A study of the beam-specific interplay effect in proton pencil beam scanning delivery in lung cancer. [2022]

2. Ireland pubmed.ncbi.nlm.nih.gov

Patient reported outcomes following proton pencil beam scanning vs. passive scatter/uniform scanning for localized prostate cancer: Secondary analysis of PCG 001-09. [2022]

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

Initial Report of Pencil Beam Scanning Proton Therapy for Posthysterectomy Patients With Gynecologic Cancer. [2020]

4. England pubmed.ncbi.nlm.nih.gov

Proton pencil beam scanning reduces secondary cancer risk in breast cancer patients with internal mammary chain involvement compared to photon radiotherapy. [2021]

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

Clinical Implementation of Preoperative Short-Course Pencil Beam Scanning Proton Therapy for Patients With Rectal Cancer. [2022]

6. England pubmed.ncbi.nlm.nih.gov

Pencil Beam Scanning Proton Therapy for Paediatric Neuroblastoma with Motion Mitigation Strategy for Moving Target Volumes. [2022]

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

Implementation of novel measurement-based patient-specific QA for pencil beam scanning proton FLASH radiotherapy. [2023]

8. Ireland pubmed.ncbi.nlm.nih.gov

Current delivery limitations of proton PBS for FLASH. [2021]

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

A case study in proton pencil-beam scanning delivery. [2018]