A Pre-Surgical PK Study of IM and Intraductally Delivered Fulvestrant

This is an open-label, non-randomized pharmacokinetic study of fulvestrant in women scheduled for mastectomy or lumpectomy. Eligible subjects will be identified with breast cancer or DCIS. The first subject of each of five groups will receive fulvestrant intramuscularly. The subsequent 5 subjects of each group will receive fulvestrant by intraductal instillation. All subjects will be monitored for systemic and local adverse events during the procedure, and following the procedure until mastectomy or lumpectomy. Subjects that receive fulvestrant will undergo serial blood draws to determine fulvestrant blood concentration levels.