Preliminary Results of a Phase 1 Dose-Escalation Trial for Early-Stage Breast Cancer Using 5-Fraction Stereotactic Body Radiation Therapy for Partial-Breast Irradiation

• DOI: 10.1016/j.ijrobp.2017.01.020
• Publication Date: 2017-01-12T19:48:09Z
• Authors: Asal Rahimi; Kimberly Thomas; Ann Spangler; Roshni Rao; Marilyn Leitch; Rachel Wooldridge; Aeisha Rivers; Stephen Seiler; Kevin Albuquerque; Stella Stevenson; Sally Goudreau; Dan Garwood; Barbara Haley; David Euhus; John Heinzerling; Chuxiong Ding; Ang Gao; Chul Ahn; Robert Timmerman
• Keywords: Cosmesis; Lumpectomy; Tolerability

To evaluate the tolerability of a dose-escalated 5-fraction stereotactic body radiation therapy for partial-breast irradiation (S-PBI) in treating early-stage breast cancer after partial mastectomy; primary objective was to escalate dose utilizing robotic system lumpectomy cavity without exceeding maximum tolerated dose.Eligible patients included those with ductal carcinoma situ or invasive nonlobular epithelial histologies and stage 0, I, II, tumor size <3 cm. Patients physicians completed baseline subsequent cosmesis outcome questionnaires. Starting 30 Gy 5 fractions escalated by 2.5 total each cohort 40 Gy.In all, 75 were enrolled, median age 62 years. Median follow-up cohorts 49.9, 42.5, 25.7, 20.3, 13.5 months, respectively. Only 3 grade toxicities experienced. There 1 dose-limiting toxicity overall cohort. Ten experienced palpable fat necrosis (4 which symptomatic). Physicians scored as excellent good 95.9%, 100%, 96.7%, 100% at 6, 12, 24 months S-PBI, whereas same periods 86.5%, 97.1%, 95.1%, 95.3%, The disagreement rates between MDs during 9.4%, 2.9%, 1.6%, 4.7%, have been no recurrences distant metastases.Dose target fractions, occurrence only toxicity. felt cosmetic results improved within first year surgery therapy. Our show minimal cosmesis; however, further is warranted future studies. This study safety, tolerability, feasibility, S-PBI treatment adjuvant setting.