Clinical trial NCT06960707: Two Versus One Week Breast Radiotherapy (RT)
Official title: Prospective Randomized Trial of Two Versus One Week Accelerated Radiotherapy (PRATO)
Study type: INTERVENTIONAL
Overall status: NOT_YET_RECRUITING
Phase: PHASE3
Conditions: Breast Cancer
Keywords: Accelerated Radiotherapy
Prone Position
Adjuvant Setting
Non-Inferiority
Concomitant Boost
Lead sponsor: Weill Medical College of Cornell University
Sponsor class: OTHER
First posted: 2025-05-07
Enrollment: 400
Sex: FEMALE
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: This study is comparing two different radiation therapy approaches for early breast cancer to see which one is better for patients. One group will receive radiation over one week (based on the FAST-FORWARD trial), and the other group will receive radiation over two weeks with an extra focused dose (called a "concomitant boost"). The study will look at how the treatments affect side effects, breast appearance, and cancer control in the breast. It also aims to find out if the two-week treatment does a better job at preventing cancer from coming back in the breast over the long term.

Detailed description: Radiotherapy: one week (Arm 1) 2600 cGy in 5 fractions whole breast radiotherapy over one week versus 2 weeks (Arm 2), 3200 cGy in 10 fractions with a concomitant tumor bed boost to 3600 cGy. In Arm 2, if no cavity is visible due to oncoplastic surgery, we will deliver 32 Gy to the whole breast only, without a boost.

Hypothesis: A regimen of whole breast radiotherapy to 2600 in five fractions, the current UK standard for early breast cancer (Arm 2), is not inferior to 3200cGy with a concomitant tumor bed boost to 3600 cGy in 10 fractions (Arm 1), in terms of acute toxicity and long-term fibrosis, breast cosmesis and local control at 2 and 5 years. It will also test the hypothesis of superior local control at 10 years in Arm 2 compared to Arm 1.

Eligibility criteria: Inclusion Criteria:

1. Women status post segmental mastectomy.
2. If unilateral, pT1-2 breast cancer excised with negative margins.
3. If bilateral, pT1-2 breast cancer excised with negative margins AND/OR pTis excised with negative margins.
4. Clinically N0 (cN0 as determined by ultrasound/SOUND criteria) or pN0-1 or Nx or sentinel node negative.
5. Ductal carcinoma in situ DCIS with negative margins (no DCIS on inked margins).
6. Women with previous contralateral treated breast cancer can be enrolled in the trial.

Exclusion Criteria:

1. Previous radiation therapy to the ipsilateral breast.
2. \>90 days from last surgery, unless s/p adjuvant chemotherapy.
3. \>60 days from last chemotherapy.
4. Male breast cancer.
5. Ongoing treatment for severe autoimmune disease.

Primary outcomes:
measure: Rate of RT-related acute toxicity
timeFrame: 1 month
Secondary outcomes:
measure: The long-term evaluations at 2 years of fibrosis based on LENT/SOMA
timeFrame: 24 months
measure: The long-term evaluations at 2 years of breast cosmesis
timeFrame: 24 months
measure: The long-term evaluations at 2 years of local control
timeFrame: 24 months
measure: The long-term evaluations at 5 years OF fibrosis based on LENT/SOMA
timeFrame: 60 months
measure: The long-term evaluations at 5 years of breast cosmesis
timeFrame: 60 months
measure: The long-term evaluations at 5 years of local control.
timeFrame: 60 months
measure: Superior local control at 10 years
timeFrame: 120 months
Other outcomes:
Locations:
city: New York
country: United States
facility: Brooklyn Methodist Hospital
state: New York
city: New York
country: United States
facility: New York Presbyterian Hospital
state: New York
city: New York
country: United States
facility: New York-Presbyterian Weill Cornell Medical College
state: New York
Study officials:
affiliation: Weill Medical College of Cornell University
name: Silvia C. Formenti, MD
role: PRINCIPAL_INVESTIGATOR
References: