OBJECTIVES:
Primary
* Determine the ipsilateral breast tumor recurrence rate in women with ductal carcinoma in situ undergoing lumpectomy followed by brachytherapy using the MammoSite\^® Radiation Therapy System.
Secondary
* Determine the early and late complication rates and cosmetic outcome in these patients after treatment.
OUTLINE: Patients undergo lumpectomy. Patients with negative tumor margins\* (no ink on tumor) undergo placement of the MammoSite\^® Radiation Therapy System at the time of lumpectomy or within 4 weeks after surgery.
NOTE: \*If positive margins are present, the surgeon may elect to resect the positive margins and then insert a new MammoSite® device if all other eligibility criteria are met.
Beginning 2-5 days after placement of the MammoSite\^®, patients undergo brachytherapy through the MammoSite\^® twice daily for 5 days (a total of 10 fractions).
After completion of study treatment, patients are followed periodically for ≥ 5 years.
