Radiation Therapy or Standard Therapy in Treating Women With Stage II Breast Cancer Who Have Undergone Mastectomy

Inclusion Criteria

• •DISEASE CHARACTERISTICS:
• •Histologically confirmed unilateral invasive breast cancer
• •* pT1, pN1, M0 disease
• •* pT2, pN1, M0 disease
• •* pT2, pN0 disease with grade III histology and/or lymphovascular invasion
• •* Multifocal breast cancer meeting both of the following criteria:
• •* Largest discrete tumor ≥ 2 cm if N0
• •* Grade III histology and/or lymphovascular invasion
• •No bilateral breast cancer
• •Axillary node negative status by axillary clearance, axillary node sampling, or sentinel node biopsy
• •* Patients with axillary node positive (1-3 positive nodes, including micrometastases\* \> 0.2 mm and ≤ 2 mm) must have had an axillary node clearance (minimum of 10 nodes removed) performed
• •* No more than 3 pathologically involved lymph nodes
• •* No internal mammary nodes visible on sentinel node scintigraphy in the absence of negative histology NOTE: \*Isolated tumor cells not counted as micrometastases
• •Underwent total mastectomy (with minimum of 1 mm margin clear of invasive cancer and DCIS) and axillary surgery with staging procedure
• •* Must have undergone adjuvant systemic chemotherapy if indicated for intermediate-risk breast cancer
• •* Patients undergoing immediate breast reconstruction allowed
• •No known BRCA1 and BRCA2 carriers
• •Hormone receptor status not specified
• •PATIENT CHARACTERISTICS:
• •Menopausal status not specified
• •Not pregnant
• •Fit for adjuvant chemotherapy, adjuvant endocrine therapy, and post-operative radiotherapy
• •No prior or concurrent malignancy except curatively treated nonmelanomatous skin cancer or carcinoma in situ of the cervix
• •PRIOR CONCURRENT THERAPY:
• •See Disease Characteristics
• •No concurrent trastuzumab
• •No prior neoadjuvant systemic therapy