Two Versus One Week Breast Radiotherapy (RT) (PRATO)

Weill Cornell Medicine (WCM)

Status and phase: Not yet enrolling; Phase 3

Conditions: Breast Cancer

Treatments: Radiation: Radiation therapy - 2 weeks; Radiation: Radiation therapy - 1 week

Study type: Interventional

Funder types: Other

Identifiers

NCT06960707

25-01028391

Details and patient eligibility

About

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.

Full 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.

Enrollment: 400 estimated patients

Sex: Female

Volunteers: No Healthy Volunteers

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.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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400 participants in 2 patient groups

ARM 1-2600 cGy in 5 fractions whole breast radiotherapy

Experimental group

Description:

Patients randomized to ARM 1 will receive 2600 cGy in 5 fractions whole breast radiotherapy over one week

Treatment:

Radiation: Radiation therapy - 1 week

ARM 2- 3200 cGy in 10 fractions with a concomitant tumor bed boost to 3600 cGy

Experimental group

Description:

Patients randomized to ARM 2 will receive 3200 cGy in 10 fractions with a concomitant tumor bed boost to 3600 cGy.

Treatment:

Radiation: Radiation therapy - 2 weeks