Radiation Therapy in Treating Women With Invasive Breast Cancer

OBJECTIVES:

Primary

• Compare the ratio between post- and pre-treatment plasma transforming growth factor-beta 1 (TGF-β) in women with invasive breast cancer undergoing hypofractionated radiotherapy vs standard-fractionated external-beam radiotherapy.

Secondary

• Establish longitudinal serum and plasma biorepository for retrospective evaluation of TGF-β and other biomarkers with special relevance to radiation response.
• Correlate pre-treatment plasma TGF-β levels with clinical fibrosis development.

OUTLINE: This is a randomized study. Patients are randomized to 1 of 2 treatment arms.

• Arm I (hypofractionated radiotherapy): Patients undergo external-beam radiotherapy once daily 5 days a week for up to 3.5 weeks (16 fractions total).
• Arm II (standard fractionated radiotherapy): Patients undergo radiotherapy as in arm I at a lower dose for up to 5 weeks (25 fractions total).

After completion of study treatment, patients are followed every 6 months for 2 years and then annually for 3 years.

PROJECTED ACCRUAL: A total of 100 patients will be accrued for this study.

DISEASE CHARACTERISTICS:

• Histologically confirmed invasive breast cancer
• Underwent lumpectomy (breast-preserving surgery) with or without adjuvant chemotherapy within the past 12 weeks

• Histologically negative surgical margins (i.e., no tumor on ink)
• Candidates for postoperative breast radiotherapy

• Determined not to need radiotherapy to regional nodes (e.g., third supraclavicular field)
• Hormone receptor status not specified

PATIENT CHARACTERISTICS:

• Female
• Menopausal status not specified
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• No history of scleroderma or systemic lupus erythematosis
• No other prior or concurrent malignancy except nonmelanoma skin cancer or carcinoma in situ of the cervix

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics
• No prior breast radiotherapy