Testing the Usual Treatment of Radiation Therapy and Hormonal Therapy to Hormonal Therapy alone for Low-Risk, Early Stage Breast Cancer, the DEBRA Trial

Summary

Objectives

PRIMARY OBJECTIVE:
I. To evaluate whether breast conservation surgery and endocrine therapy results in a non-inferior rate of invasive or non-invasive ipsilateral breast tumor recurrence (IBTR) compared to breast conservation with breast radiation and endocrine therapy.

SECONDARY OBJECTIVES:
I. To evaluate whether breast conservation surgery and endocrine therapy inclusive of any second breast conservation surgery for salvage of IBTR results in a non-inferior rate of overall breast conservation compared to breast conserving surgery, endocrine therapy, and radiation for IBTR.
II. To evaluate whether breast conservation surgery and endocrine therapy results in a non-inferior rate of invasive ipsilateral breast tumor recurrence (IIBTR) compared to breast conservation, breast radiation, and endocrine therapy.
III. To evaluate whether breast conservation surgery and endocrine therapy results in a non-inferior relapse free interval (RFI) compared to breast conservation, breast radiation, and endocrine therapy.
IV. To evaluate whether breast conservation surgery and endocrine therapy results in a non-inferior distant disease-free survival (DDFS) compared to breast conservation, breast radiation, and endocrine therapy.
V. To evaluate whether breast conservation surgery and endocrine therapy results in a non-inferior overall survival (OS) compared to breast conservation, breast radiation, and endocrine therapy.
VI. To evaluate whether there is a difference in patient-reported breast pain in women who do and do not receive breast radiation.
VII. To evaluate whether there is a difference in patient-reported worry about recurrence in women who do and do not receive breast radiation.
VIII. To evaluate whether adherence to endocrine therapy following breast conservation surgery alone is non inferior compared to endocrine therapy with breast conservation surgery and breast radiation.

OUTLINE: Patients are randomized to 1 of 2 arms.

ARM I: Within 12 weeks of the last breast cancer surgery, patients undergo external beam radiation therapy. Patients also receive endocrine therapy for a minimum of 5 years initiated before, during, or after completion of radiation therapy at the discretion of the investigator. Endocrine therapy may include tamoxifen, anastrozole, letrozole, exemestane, or luteinizing hormone-releasing hormone (LHRH) agonist/antagonist. Treatment continues in the absence of disease progression or unacceptable toxicity. Patients undergo mammogram or magnetic resonance imaging (MRI) as well as optional blood sample collection throughout the trial.

ARM II: Patients receive endocrine therapy for a minimum of 5 years at the discretion of the investigator. Endocrine therapy may include tamoxifen, anastrozole, letrozole, exemestane, or LHRH agonist/antagonist. Treatment continues in the absence of disease progression or unacceptable toxicity. Patients undergo mammogram or MRI as well as optional blood sample collection throughout the trial.

After completion of study treatment, patients are followed up every 6 months for 24 months, and then every 12 months from year 3 through year 10 after randomization.