SABER Study for Selected Early Stage Breast Cancer

"Preoperative SABER: Participants will be treated with an assigned dose level of preoperative SABER, delivered in once a day, 5 fractions given on non-consecutive days, over a period of 2 weeks. In this phase I study, starting with dose level II, a dose level of preoperative SABER will be assigned per study dose-escalation design, treating 2 to 6 patients per dose level. The tested doses are the following:~* Dose Level I: 35 Gy (5 fractions of 7 Gy)~* Dose Level II (Starting Dose): 40 Gy (5 fractions of 8 Gy)~* Dose Level III: 45 Gy (5 fractions of 9 Gy)~* Dose Level IV: 50 Gy (5 fractions of 10 Gy)"