RecruitingNot ApplicableNCT07020780

5 fr Ultrahypofractionated WBI and SIB for Breast Cancer With Unfavorable Characteristics

Five Fractions Ultrahypofractionated Whole Breast Radiotherapy and Simultaneous Integrated Boost to the Tumor Bed, for Breast Cancer Patients With Unfavorable Characteristics

Sponsor

IRCCS San Raffaele

Enrollment

458 participants

Start Date

Jul 25, 2025

Study Type

INTERVENTIONAL

Conditions

Breast Cancer

Summary

This is a prospective, randomized, single-center, non-inferiority interventional clinical trial comparing whole breast irradiation (WBI) to a total dose of 26 Gy in 5 fractions with simultaneous integrated boost (SIB) to the tumor bed to a total dose of 30 Gy, and WBI to a total dose of 40.05 Gy in 15 fractions with SIB to the tumor bed to a total dose of 48 Gy (standard treatment), for young or unfavorable breast cancer patients.

Eligibility

Sex: FEMALEMin Age: 18 YearsMax Age: 70 Years

Inclusion Criteria9

Histological diagnosis of breast cancer
Patients younger than 40 years regardless of histological subtype, or patients between 40 and 70 years with lobular carcinoma, histological subtypes Luminal B Her2 positive, or with hormone receptors negative and Her2 positive (ErbB2), or triple negative (TNBC)
Signed informed consent
Clinical stage T1-T3, Nx-N3
Negative surgical margins (≥ 0.2 cm)
Clinical M0 in the previous 3 months
PS (ECOG) ≤2
No previous thoracic radiotherapy
Fertile women using contraceptive methods started during oncological treatment

Exclusion Criteria13

Patients with favorable characteristics (Luminal A, Luminal B Her2 negative, ≥ 40 years) undergoing partial irradiation
Patients who have undergone mastectomy
Multicentric tumors
Positive or close surgical margins (\<0.2 cm)
BRCA1/2 positive (only if known)
Serious systemic diseases
Mental or other disorders that may prevent the patient from signing the informed consent
Previous invasive tumor, except skin cancer (excluding melanoma) unless the patient has been disease-free for at least 3 years (for example carcinoma in situ of the oral cavity or bladder)
Collagen or autoimmune diseases (systemic lupus erythematosus, rheumatoid arthritis, scleroderma, Sjogren's syndrome)
Evidence of distant metastases (M1)
Contraindication to treatment systemic
Pregnant women
Non-compliance with the dose limits established in the treatment plan

Interventions

RADIATIONAdjuvant 5 fractions whole breast irradiation with simultaneous integrated boost to the tumor bed

Experimental arm (arm 1-five fractions WBI) patients will be treated to a total dose (TD) of 26 Gy in 5 fractions to whole breast, and a simultaneous integrated boost (SIB) to a TD of 30 Gy to the tumor bed, while arm 2-fifteen-fractions WBI patients with 40 Gy/15 fractions to PTV, and 48 Gy SIB to the tumor bed.