Lumpectomy Followed By Intraoperative Electron Radiation Therapy (IOERT)

Evaluate local and distant recurrence rates and cosmetic outcomes. Both clinical evaluation
of cosmetic outcome by the Surgeon, and subjective impression of cosmetic outcome by the
patient, are evaluated using questionnaire.

Local recurrence is evaluated under the same imaging protocol used for Whole breast
radiation.

Inclusion Criteria:

- Patient agrees to breast conservation therapy (segmental resection, partial
mastectomy, and radiation therapy) as the treatment for their breast cancer

- Patient agrees to evaluation of the axilla with sentinel lymph node biopsy

- Peri or post-menopausal women age > 50, defined as women who have experienced no
menstrual period in the past 6 months or more

- BRCA1 and 2 gene mutation negative, if tested. [genetic testing is NOT required based
upon personal or family history]

- Unifocal (unicentric), invasive ductal carcinoma or favorable sub-types (mucinous,
tubular, colloid) < 2.0 cm in diameter, primary T-stage of Tis or T1 (AJCC criteria)

- Grade 1, 2, or 3 acceptable

- Associated LCIS is allowed

- Pure DCIS allowed if <2.5 cm, low to intermediate nuclear grade and resected margins
negative at > 3 mm (per ASTRO criteria)

- Estrogen receptor (ER) status of positive

- Patient has clear margins >2 mm on gross pathologic examination

- Patient is node-negative, defined as N0 (i-) or N0 (i+)

- Patient must be deemed functionally and mentally competent to understand and sign the
informed consent

- Neoadjuvant hormonal therapy is allowed if all other ASTRO suitable criteria have been
met prior to onset of hormonal therapy

Exclusion Criteria:

- Prior breast malignancy or other malignancy if metastatic, or with expected survival
of < 5 years

- Immunocompromised status

- Pregnancy

- Women with an active connective tissue disorder (i.e. scleroderma, lupus and others)

- Breast cancer that involves the skin or chest wall, locally advanced breast cancer

- Invasive lobular carcinoma

- Evidence of lymphovascular invasion (LVI)

- Invasive carcinoma with extensive intraductal component (EIC)

- Neoadjuvant chemotherapy

- Patients with 1 or more positive lymph node determined during surgery with sentinel
node and/or axillary dissection

- Someone who is not a candidate for breast conserving management, i.e., prior whole
breast radiation therapy