Ultra-Hypofractionated vs. Moderately Hypofractionated Proton Therapy for Early Breast Cancer After Lumpectomy

NCT ID: NCT07135661

Last Updated: 2025-08-22

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: NA
• Total Enrollment: 312 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2024-10-10
• Study Completion Date: 2029-10-31

Brief Summary

Breast-conserving surgery (BCS) followed by whole-breast irradiation (WBI) remains the standard therapeutic approach for early-stage breast cancer. Long-term follow-up data from the FAST trial (10-year analysis) demonstrated that the 28.5 Gy/5-fraction regimen exhibited comparable adverse effects to the conventional 50 Gy/25-fraction regimen, with no statistically significant differences in photographic cosmetic assessments at 2 and 5 years post-treatment. The FAST-Forward trial demonstrated comparable 5-year ipsilateral breast tumor recurrence rates (IBTR) and incidence of radiation-related toxicities between ultra-hypofractionated whole-breast irradiation (UH-WBI; 26 Gy in 5 fractions over 1 week) and moderately hypofractionated whole-breast irradiation (MH-WBI; 40 Gy in 15 fractions over 3 weeks). Additionally, no statistically significant difference in cosmetic outcomes was observed between the two regimens at the 2-year follow-up.

Proton radiotherapy enables precise dose delivery to tumor targets while minimizing radiation exposure to surrounding normal tissues, thereby reducing treatment-related toxicities. However, current clinical protocols predominantly employ conventional fractionation for proton therapy, with a paucity of robust evidence evaluating the efficacy and safety of ultra-hypofractionated proton radiotherapy in breast cancer patients. This prospective randomized controlled trial aims to establish high-level scientific evidence for the clinical application of ultra-hypofractionated proton radiotherapy following BCS, ensuring non-inferiority in oncologic control, toxicity profiles, and cosmetic preservation compared to standard regimens.

Conditions

Breast Cancer; Proton Therapy

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

moderate hypofractionated proton radiotherapy

Whole Breast Irradiation, at 40 Gy(RBE) in 15 fractions, tumor bed SIB to 48Gy(RBE)

Group Type: ACTIVE_COMPARATOR

moderate hypofractionated proton radiotherapy

Intervention Type: RADIATION

moderate hypofractionated proton radiotherapy: Whole Breast Irradiation, at 40 Gy(RBE) in 15 fractions, tumor bed SIB to 48Gy(RBE)

ultra-hypofractionated proton radiotherapy

Whole breast radiotherapy, 26 Gy(RBE) in 5 fractions，tumor bed boost with 10Gy(RBE) in 2 fractions.

Group Type: EXPERIMENTAL

ultra-hypofractionated proton radiotherapy

Intervention Type: RADIATION

Ultra-hypofractionated proton radiotherapy:Whole breast radiotherapy, 26 Gy(RBE) in 5 fractions，tumor bed boost with 10Gy(RBE) in 2 fractions.

Interventions

moderate hypofractionated proton radiotherapy

moderate hypofractionated proton radiotherapy: Whole Breast Irradiation, at 40 Gy(RBE) in 15 fractions, tumor bed SIB to 48Gy(RBE)

Intervention Type: RADIATION

ultra-hypofractionated proton radiotherapy

Ultra-hypofractionated proton radiotherapy:Whole breast radiotherapy, 26 Gy(RBE) in 5 fractions，tumor bed boost with 10Gy(RBE) in 2 fractions.

Intervention Type: RADIATION

Eligibility Criteria

Inclusion Criteria

1. Age ≥ 40 years

2. Pathologically (cytologically or histologically) confirmed unilateral primary invasive breast carcinoma

3. Breast conserving surgery + sentinel lymph node biopsy/axillary lymph node dissection, pathological stage pT1-2N0M0，negative margins (≥ 2 mm)

4. No distant metastasis confirmed by CT, MRI, bone scan, and PET/CT

5. No prior radiation therapy to the ipsilateral chest or breast

6. ECOG 0 ~ 2 or KPS ≥ 70

Exclusion Criteria

1. Without pathology diagnosis

2. Positive margins or close margins (< 2mm)

3. Lymph nodes or distant metastasis

4. Bilateral breast cancer or patients with a history of contralateral breast cancer

5. Prior radiation therapy to the ipsilateral chest or breast

6. Pregnancy (confirmed by serum or urine β-HCG test) or lactation

• Minimum Eligible Age: 40 Years
• Eligible Sex: FEMALE
• Accepts Healthy Volunteers: No

Sponsors

Shanghai Proton and Heavy Ion Center

OTHER

Sponsor Role: lead

Responsible Party

Qing Zhang,MD

Principal Investigator

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

Shanghai Proton and Heavy Ion Center

Shanghai, , China

Site Status: RECRUITING

Countries

China

Central Contacts

Ping Li

Role: CONTACT

ping.li@sphic.org.cn

+86 02138296666

Facility Contacts

Ping Li, M.D.

Role: primary

ping.li@sphic.org.cn

+86 021-38296538

Other Identifiers

SPHIC-TR-BCa2024-02

Identifier Type: -

Identifier Source: org_study_id