IDE not submitted

This phase II trial studies how well radiation therapy works in treating post-menopausal women with early stage breast cancer undergoing surgery. Radiation therapy uses high energy x rays to kill tumor cells. This may be an effective treatment for breast cancer.

PRIMARY OBJECTIVE:

I. For select patients with early stage breast cancer undergoing wide local excision followed by single fraction radiation therapy (SFRT), we will evaluate rates of observer-rated toxicity, cosmetic outcomes and patient satisfaction, objective measures of toxicity and quality of life as well as delivery of intended dose.

SECONDARY OBJECTIVE:

I. Locoregional control reported at five years.

OUTLINE:

Patients undergo wide local excision breast surgery and SFRT over 60-100 minutes once negative margins are obtained.

After completion of study treatment, patients are followed at 1 week, 1 month, 3 months, and then every 6 months for 2 years.

Inclusion Criteria:

• Core needle biopsy (e.g. Mammotome, core, stereotactic, ultrasound guided) showing invasive mammary cancer (with or without concomitant ductal carcinoma or lobular carcinoma in situ) or ductal carcinoma in situ; acceptable histologic types of invasive mammary cancer include ductal, tubular, mucinous, papillary, cribriform and "NOS" (not otherwise specified); invasive lobular cancer is excluded

• Age >= 50 years and postmenopausal with no menses for at least one year prior to study enrollment

• Age > 70 years with invasive breast cancer clinical size =< 3 cm OR Age 50 - 70 years with invasive breast cancer clinical size =< 1.5 cm OR Age >= 50 years and postmenopausal with any grade ductal carcinoma in situ (DCIS) clinical extent =< 1.5 cm (clinical tumor size will be determined by pre-operative breast imaging-mammography, ultrasound and/or magnetic resonance imaging; in cases of multiple measurements, the largest recorded single dimension will be used to determine eligibility)

• Hormone receptor status

  • Estrogen or progesterone receptor positive or
  • Estrogen and progesterone receptor negative and clinical tumor size =< 1.0 cm

• Human epidermal growth factor receptor 2 (HER2)/neu negative on the core biopsy analysis defined as 0 or 1+ by immunohistochemistry or not amplified by fluorescent in situ hybridization analysis

• Tumor >= 0.5 cm from skin as defined by breast ultrasound

• Unicentric tumor

• Axillary lymph nodes negative by pre-operative physical examination in all cases and pathologic examination from surgery for invasive disease

• Negative surgical margins, defined as no margin-labeling ink on tumor cells from margin evaluation

Exclusion Criteria:

• Initial core biopsy showing invasive lobular cancer
• Estrogen receptor and progesterone receptor negative tumor with clinical size > 1 cm
• Any Her 2+ breast cancer (immunohistochemistry 3+; or amplified by fluorescence in situ hybridization [FISH])
• Cancer in a patient with a known inherited susceptibility mutation in breast cancer (BRCA)1 or BRCA2
• Multicentric breast cancer (two foci of known cancer in the breast separated by greater than 5 cm, or in separate quadrants
• Clinically or pathologically positive axillary lymph nodes
• Any prior breast cancer
• Prior breast radiation therapy