Radiation Therapy (WBI Versus PBI) in Treating Women Who Have Undergone Surgery For Ductal Carcinoma In Situ or Stage I or Stage II Breast Cancer

DISEASE CHARACTERISTICS:

   - Histologically confirmed ductal carcinoma in situ (DCIS*) or invasive* adenocarcinoma
   of the breast

      - Stage 0, I, or II disease

         - Stage II tumors must be ≤ 3 cm

      - Gross disease must be unifocal

         - Microscopic multifocality allowed provided total pathological tumor size is
         ≤ 3 cm

      - No proven multicentric carcinoma in more than 1 quadrant or separated by ≥ 4 cm

      - No non-epithelial breast malignancies (e.g., sarcoma or lymphoma) NOTE: *Patients
      who are 50 years of age and over with DCIS regardless of hormone receptor status
      AND patients with invasive breast cancer meeting all of the following criteria: ≥
      50 years of age, node-negative, and hormone-receptor positive status will not be
      enrolled in study after 12/30/2006

   - Prior axillary staging required for patients with invasive breast cancer, including 1
   of the following:

      - Sentinel node biopsy alone (if sentinel node is negative)

      - Sentinel node biopsy followed by axillary dissection or sampling with ≥ 6
      axillary nodes (if sentinel node is positive)

      - Axillary dissection alone with ≥ 6 axillary nodes

   - No more than 3 positive axillary nodes

      - No axillary nodes with definite evidence of microscopic or macroscopic
      extracapsular extension

      - No positive non-axillary sentinel nodes (intramammary nodes are staged as
      axillary nodes)

      - No palpable or radiographically suspicious ipsilateral or contralateral axillary,
      supraclavicular, infraclavicular, or internal mammary nodes unless there is
      histologic confirmation that these nodes are negative for tumor

   - Must have undergone lumpectomy

      - Resected margins histologically free of tumor

      - Re-excision of surgical margins allowed

      - Target lumpectomy cavity clearly delineated AND target lumpectomy/whole breast
      reference volume ≤ 30% based on postoperative pre-randomization CT scan

      - Final surgery (i.e., lumpectomy, re-excision of margins, or axillary staging
      procedure) within the past 42 days

   - No suspicious microcalcifications, densities, or palpable abnormalities in the
   ipsilateral or contralateral breast unless biopsied and found to be benign

   - No Paget's disease of the nipple

   - No history of invasive breast cancer or DCIS

      - Prior lobular carcinoma in situ treated by surgery alone allowed

   - No synchronous bilateral invasive or non-invasive breast cancer

   - Partial breast irradiation deemed technically deliverable by radiation oncologist at a
   credentialed facility

   - Must have undergone a history and physical exam within the past 4 months AND a
   bilateral mammogram within the past 6 months

   - Hormone receptor status:

      - Estrogen receptor (ER) status known

      - Progesterone status known if ER analysis is negative

      - Marginal or borderline results are considered positive

PATIENT CHARACTERISTICS:

Age

   - 18 and over

Sex

   - Female

Menopausal status

   - Premenopausal or postmenopausal

Performance status

   - Not specified

Life expectancy

   - At least 10 years, excluding diagnosis of breast cancer

Hematopoietic

   - Not specified

Hepatic

   - Not specified

Renal

   - Not specified

Other

   - Not pregnant or nursing

   - Negative pregnancy test

   - Fertile patients must use effective non-hormonal contraception

   - No other malignancy within the past 5 years except previously treated carcinoma in
   situ of the cervix or colon, melanoma in situ, or basal cell or squamous cell skin
   cancer

      - Deemed to be at low risk for recurrence

   - No collagen vascular disease (e.g., systemic lupus erythematosus or scleroderma),
   specifically dermatomyositis with a creatine phosphokinase (CPK) level above normal,
   or active skin rash

   - No psychiatric or addictive disorder that would preclude study therapy

PRIOR CONCURRENT THERAPY:

Biologic therapy

   - No prior biologic therapy for this malignancy

Chemotherapy

   - No prior chemotherapy for this malignancy

   - No concurrent chemotherapy during study radiotherapy

Endocrine therapy

   - No prior hormonal therapy for this malignancy unless total duration of hormonal
   therapy was no more than 28 days before randomization

   - Concurrent hormonal therapy allowed provided it is not administered during
   chemotherapy

   - No concurrent raloxifene, tamoxifen, or other selective estrogen receptor modulating
   drugs

   - No concurrent hormone replacement therapy

   - No concurrent Femring^®

Radiotherapy

   - No prior radiotherapy for this malignancy

   - No prior breast or thoracic radiotherapy

   - No concurrent brachytherapy boosts

   - No concurrent intensity modulated radiotherapy

   - No concurrent regional nodal irradiation

Surgery

   - See Disease Characteristics

   - No prior breast implants

      - Patients who have had implants removed are eligible

Other

   - No other concurrent anticancer therapy