Radiation Therapy in Treating Women Who Have Undergone Surgery for Early-Stage Invasive Breast Cancer

DISEASE CHARACTERISTICS:

* Histologically proven invasive carcinoma of the breast

  * No evidence of T4, N2-3, or M1 disease prior to surgery
  * Node positive or high-risk node negative
* Prior breast-conserving therapy (BCT) (e.g., lumpectomy, partial mastectomy, or segmental mastectomy) and axillary node dissection or sentinel node biopsy required and must be a candidate for breast radiotherapy after BCT

  * Normally patients should have microscopically clear resection margins and those with positive margins should undergo reexcision
  * Patients with microscopically focally positive margins (defined as no greater than 3 times high power fields) are candidates for breast radiotherapy plus a boost to the lumpectomy site
  * Patients with prior sentinel node dissection eligible if node negative, but still meet high-risk criteria

    * If node positive, then a level I and II axillary dissection must be performed
  * No evidence of residual disease in axilla after dissection
* Must be treated with currently accepted adjuvant systemic chemotherapy and/or hormonal therapy
* High risk of regional and systemic recurrence due to one of the following:

  * Pathologically positive axillary lymph nodes
  * Pathologically negative axillary lymph nodes with one of the following:

    * Primary tumor greater than 5 cm
    * Primary tumor greater than 2 cm and less than 10 axillary lymph nodes excised and one of the following:

      * Estrogen receptor negative
      * Skarf-Bloom-Richardson grade 3
      * Lymphovascular invasion
* Hormone receptor status:

  * Estrogen and progesterone receptor status known

PATIENT CHARACTERISTICS:

Age:

* 16 and over

Sex:

* Female

Menopausal status:

* Premenopausal or postmenopausal

Performance status:

* ECOG 0-2

Life expectancy:

* At least 5 years

Hematopoietic:

* Not specified

Hepatic:

* SGOT and/or SGPT no greater than 3 times upper limit of normal (ULN)\*
* Alkaline phosphatase no greater than 3 times ULN\* NOTE: \* Patients with laboratory values greater than 3 times ULN may still be eligible if no metastatic disease by imaging examinations

Renal:

* No serious nonmalignant renal disease

Cardiovascular:

* No serious nonmalignant cardiovascular disease

Pulmonary:

* No serious nonmalignant pulmonary disease

Other:

* Not pregnant or nursing
* Fertile patients must use effective contraception
* No other serious nonmalignant disease (e.g., systemic lupus erythematosus or scleroderma) that would preclude definitive surgery or radiotherapy
* No other malignancy except:

  * Nonmelanomatous skin cancer
  * Carcinoma in situ of the cervix or endometrium
  * Contralateral noninvasive breast cancer (unless prior radiotherapy to the contralateral breast)
  * Invasive carcinoma of the cervix, endometrium, colon, thyroid, or melanoma that was curatively treated at least 5 years prior to study participation
* No psychiatric or addictive disorder that would preclude informed consent or study compliance

PRIOR CONCURRENT THERAPY:

Biologic therapy:

* Not specified

Chemotherapy:

* See Disease Characteristics
* Concurrent standard adjuvant chemotherapy allowed

Endocrine therapy:

* See Disease Characteristics
* Concurrent standard adjuvant hormonal therapy allowed

Radiotherapy:

* See Disease Characteristics

Surgery:

* See Disease Characteristics