NCT06960707

Two Versus One Week Breast Radiotherapy (RT)

Prospective Randomized Trial of Two Versus One Week Accelerated Radiotherapy (PRATO)

• Status: Recruiting
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 400 (estimated)
• Sponsor: Weill Medical College of Cornell University · Academic / Other
• Sex: Female
• Age: —
• Healthy volunteers: Not accepted

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.

Conditions

• Breast Cancer

Interventions

Type	Name	Description
RADIATION	Radiation therapy - 1 week	2600 cGy whole breast radiotherapy in five fractions (Arm 1) over 1 week
RADIATION	Radiation therapy - 2 weeks	3200 cGy whole breast radiotherapy with a concomitant tumor bed boost to 3600 cGy in 10 fractions (Arm 2) over 2 weeks. 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.

Timeline

• Start date: 2025-04-29
• Primary completion: 2030-12-31
• Completion: 2040-12-31
• First posted: 2025-05-07
• Last updated: 2025-07-25

Locations

3 sites across 1 country: United States

Regulatory

• FDA-regulated device study