Inclusion Criteria:

- Diagnosis of invasive breast cancer - the following information must be known based
on the needle core biopsy: tumor grade, hormone receptor status, and HER2/neu status.
Patients with a previous history of either ipsilateral or contralateral excisional
biopsy are not excluded. However, patients are excluded if an excisional biopsy was
used to diagnose the current breast cancer.

Note: Subjects undergoing sentinel lymph node (SLN) biopsy will not be excluded from this
research study. It is not expected that radiofrequency ablation (RFA) will interfere with
the SLN procedure because other studies have demonstrated the accuracy of sentinel node
staging after excisional biopsy. The axillary staging in these subjects will be noted.

- Tumor size < 2 centimeters by mammogram or ultrasound, with ultrasound being the
preferred method of evaluation. Measurements by physical exam should also be
recorded. If mammogram and ultrasound are discordant, then the imaging modality that
determines the largest tumor size will be used to determine eligibility.

- Ultrasound measurements: Distance from tumor to skin must be > 1 cm; distance from
tumor to chest wall must be > 1 cm. The RFA procedure, which burns the tumor, may
also burn the skin or muscle if it is too close (< 1cm).

- Laboratory values within 2 weeks of registration: platelet count ≥ 50,000; INR ≤ 1.6;
serum creatinine ≤ 1.5 mg/dL; glomerular filtration rate (GFR) ≥ 60 ml/min/m^2

- Age 18 years or older

- Women must not be pregnant due to MR scanning of pregnant women is not FDA approved.
All females of childbearing potential must have a urine study within 2 weeks prior to
registration to rule out. Breast feeding must be discontinued prior to study entry.

Exclusion Criteria:

- Subjects for whom neo-adjuvant therapy is planned will be excluded from this study

- Patients with history of severe asthma and/or allergies will be excluded to avoid
potential adverse reactions to the MRI contrast agent (Gd-DTPA)

- Patients with pacemakers, any ferromagnetic implants or other ferromagnetic objects
will be excluded

- Patients with obesity (>250 pounds) will be excluded due to the limited diameter of
the magnet bore tube

- Patients with history of severe claustrophobia will be excluded

Patient must give written informed consent indicating the investigational nature of the
study and its potential risks