Radiation Therapy in Treating Women With Locally Recurrent Breast Cancer Previously Treated With Repeat Breast-Preserving Surgery

DISEASE CHARACTERISTICS: * Histologically confirmed locally recurrent breast carcinoma consistent with the following cell types: * Invasive ductal breast carcinoma * Medullary ductal breast carcinoma * Tubular ductal breast carcinoma * Mucinous ductal breast carcinoma * Lobular breast carcinoma * Ductal carcinoma in situ (DCIS) * No Paget disease of the nipple * Target lumpectomy cavity must be clearly defined and the target lumpectomy cavity/ whole-breast reference volume must be \< 30% based on a post-operative, pre-treatment CT scan * Tumor size ≤ 3 cm in greatest dimension on pathologic specimen * Negative histologic margins of resection and no tumor on ink following breast-preserving surgery of local recurrence (Re-excision is permitted to achieve negative margins) * Axilla negative or ≤ 3 positive lymph nodes without extracapsular extension * If the in-breast recurrence is DCIS and/or microinvasive disease, a sentinel lymph node (SLN) evaluation is not required, but if performed: * Patients with a negative sentinal lymph node (SLN) biopsy are eligible for enrollment * Patients with a positive SLN biopsy require an axillary lymph node (ALN) dissection (ALND is not required if the SLN is not identified) * Patient is eligible if 0-3 positive ALNs without extracapsular extension is documented * If the in-breast recurrence is invasive disease and: * No prior ALN dissection or SLN dissection only: * Patient is required to undergo axi…