Partial-Breast Radiation Therapy in Treating Women With Early-Stage Breast Cancer

You may be eligible if

• DISEASE CHARACTERISTICS:
• Histologically confirmed ductal carcinoma in situ (DCIS) of the breast or invasive breast adenocarcinoma
• * Stage 0, I, or II (T2, N0; tumor size ≤ 3 cm) disease
• * Pathologic staging of the axilla preferred
• * Clinical staging of the axilla allowed for patients ≥ 70 years of age with hormone receptor-positive tumors
• Unicentric tumor
• * Microscopic multifocality allowed as long as the total tumor size is ≤ 3 cm
• Must have undergone lumpectomy as definitive surgery
• * Negative surgical margins, defined as no tumor at the inked margin of resection after final surgery
• * Re-excision to obtain negative margins allowed
• Must have adequate skin spacing between balloon surface and surface of the skin and lung (≥ 7 mm)
• No multicentric carcinoma (invasive or DCIS) in more than one quadrant
• No clinically or pathologically positive regional lymph nodes
• No extensive intraductal component, defined as DCIS extending beyond the primary invasive component into normal breast parenchyma and composing \> 25% of the primary tumor
• Hormone receptor status not specified
• PATIENT CHARACTERISTICS:
• Menopausal status not specified
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• No collagen-vascular disease, including any of the following:
• * Dermatomyositis
• * Systemic lupus erythematosus
• * Scleroderma-mixed connective tissue disease
• PRIOR CONCURRENT THERAPY:
• See Disease Characteristics