The study is designed to assess the accuracy of patient breast reproducibly using the revised BCID. This study would provide data for target verification and quality assurance to eventually allow treatment of breast cancer patients for either a TBB or accelerated partial breast irradiation. The BCID is a low-risk device similar to immobilization devices used routinely in radiotherapy for other disease sites.

Breast conserving therapy (BCT) has become the standard of care for treating early-stage breast cancers based on six prospective randomized trials with 20 years of follow-up data (Fisher). During lumpectomy, the surgeon removes the tumor and a surrounding rim of normal tissue (margin), leaving surgical clips to help designate the resection bed. Radiation treatment is directed at the whole breast for 5 1/2 weeks and is generally followed by a 1-2 week boost directed at the lumpectomy site plus a margin of normal breast tissue. The benefit of adding the tumor bed boost, (TBB) has been shown in two studies to decrease local failures [Romestaig; Bartelink].

Studies have evaluated the role of radiation following lumpectomy in very select groups which have not been able to define a group who do not benefit from the addition of radiotherapy. In the group of patients who received surgery alone, 85% of the breast recurrences occurred in the tumor bed. Due to these two facts, radiotherapy directed only at the tumor bed has been evaluated. Treating this smaller tumor volume has allowed higher doses of radiation to be delivered safely shortening the treatment course from 6-7 weeks to one week.

Inclusion Criteria:

1. The patient must consent to be in the study and have signed an IRB-approved consent form.
2. The patient must have a diagnosis of invasive or non-invasive breast cancer.
3. The patient must be planned for or have already had breast conservation surgery (i.e. lumpectomy).

4 Age > 18. 5. There are at least two metal clips in the surgical cavity placed at the time of surgery for guiding the radiation oncologist in delineating the target of irradiation; or one radiographic clip placed at the time of stereotactic core needle biopsy with the intact tumor.

6. Patients who have already been treated by radiation therapy and are being seen in follow-up can also participate

Exclusion Criteria:

1. Male gender
2. Patients who cannot be set up comfortably in the prone position (e.g. physical disability)
3. Tumor/lumpectomy site located in a portion of the breast that cannot be visualized easily on the CT scan (e.g. superior portion of the upper outer quadrant).
4. Mastectomy was or is the recommended surgical approach.

Cancer Center, Primary Care Clinic

Geometric Reproducibility of the Lumpectomy Cavity Using a Breast Cup Immobilization Device II

30 days