Study may not be clinically relevant at this time.

Eligible patients will be female, ages 18 and older and have a diagnosis of Clinical T1 or T2 invasive breast cancer with no suspicious palpable adenopathy. Patients will undergo standard of care lumpectomy without sentinel node biopsy and whole breast radiation, followed by chemotherapy.

Sentinel node biopsy is also considered standard care when patients have localized breast cancer. Treatment can often be influenced by whether the results of the biopsy show cancer or not. However, the biologic factors of the primary tumor have become more important in determining treatment recommendations in women with clinically node negative breast cancer.

The primary objective of the study is to determine the locoregional recurrence rate in patients with clinically node negative T1 and T2 breast cancer treated with systemic chemotherapy and whole breast irradiation in whom biopsy of the sentinel node is not performed. A locoregional recurrence is defined as any recurrence in the ipsilateral axillary nodes or in the supraclavicular nodes.

After surgery, a patient will receive standard of care radiation on her affected breast and chemotherapy. A physical examination of the affected breast and regional lymph nodes will be conducted every six months for the first two years of follow up and then yearly for the last 3 years of follow up. Imaging of the affected breast will occur every 12 months after surgery per standard of care.

Inclusion Criteria:

• Female age 18 and older, not pregnant or lactating
• Clinical T1 or T2 invasive cancer with no suspicious palpable adenopathy
• If abnormal axillary nodes are seen on preoperative imaging, a negative fine needle aspiration or core biopsy is required for study entry.
• Planned treatment with breast conserving surgery and whole breast irradiation
• Chemotherapy required postoperatively based on patient and tumor characteristics at diagnosis

Exclusion Criteria:

• Patients with suspicious palpable axillary adenopathy
• Patients with biopsy demonstrating axillary nodal metastases
• Patients with treatment by mastectomy
• Patients who have undergone neoadjuvant chemotherapy
• Patients with co-morbidities rendering the patient not a candidate for chemotherapy, surgery, or irradiation
• Patients treated with accelerated partial breast irradiation (APBI)
• Patients with contraindication to radiation