The purpose of this national, multi-site study is to determine the safety and effectiveness of the Contura catheter in breast cancer patients undergoing accelerated partial breast irradiation.

The Cancer Center of Irvine is one of the busiest centers in the United States for Contura accelerated partial breast irradiation.

Inclusion Criteria:

• Able and willing to sign informed consent
• Age 50 or older at diagnosis
• Life expectancy greater than 10 years (excluding diagnosis of breast cancer)
• Surgical treatment of the breast must have been lumpectomy. The margins of the resected specimen must be histologically free of tumor (negative surgical margins per NSABP criteria)
• On histologic examination, the tumor must be DCIS and/or invasive breast carcinoma
• For patients with invasive breast cancer, an axillary staging procedure must be performed [either sentinel node biopsy or axillary dissection (with a minimum of 6 axillary nodes removed), and the axillary node(s) must be pathologically negative]
• The T stage must be Tis, T1, or T2. If T2, the tumor must be less than or equal to 3.0 cm in maximum diameter
• Estrogen receptor positive tumor

Exclusion Criteria:

• Age < 50 at diagnosis (regardless of histology)
• Pregnant or breast-feeding
• Active collagen vascular disease
• Paget's disease of the breast
• Prior history of DCIS or invasive breast cancer
• Prior breast or thoracic radiation therapy for any condition
• Multicentric carcinoma (DCIS or invasive)
• Synchronous bilateral invasive or non-invasive breast cancer
• Surgical margins that cannot be microscopically assessed or that are positive
• Positive axillary node(s)
• T stage of T2 with the tumor > 3 cm in maximum diameter or a T stage of T3 or T4
• Estrogen receptor negative tumor