Accuray Incorporated announced that data from a prospective, phase II trial of 338 women with low-risk breast cancer showed 98.8% had local disease control seven years after receiving once-daily accelerated partial breast irradiation (APBI) delivered with the TomoTherapy System. The study, published online in the International Journal of Radiation Oncology Biology Physics, also reported that the once-daily schedule was associated with a very low incidence of acute and late toxicities. The TomoTherapy platform, including the next-generation Radixact® System, is the first in the world capable of helical radiation delivery. Image-guided, intensity-modulated radiation therapy (IG-IMRT) is continuously delivering from a full 360 degrees around the patient as the treatment table also moves at a deliberate pace, providing greater control of the radiation dose so it conforms precisely to the tumor and helps minimize dose to healthy tissue. This precision enables medical care teams to deliver hypofractionated treatment regimens - a higher dose per fraction in fewer fractions than conventional schedules - such as APBI, with increased confidence. Enhanced precision enables excellent long-term results: study highlights: Once-daily breast APBI delivered with the TomoTherapy System demonstrated the following: Ipsilateral breast tumor recurrence (IBTR) free control was 99.4% at a median follow-up of 76 months. This is important because patients with IBTR may be at high risk for subsequent distant metastasis; Locoregional control (no recurrence in ipsilateral breast as well as in regional nodes) was 98.8% at a median follow-up of 76 months; Progression-free survival was 98.4% and 92% at 5 and 10 years; Treatments were very well tolerated with minimal acute or late side effects. Importantly, there were no cases observed of late toxicity such as pneumonitis or rib fractures; More than 95% of patients and their physicians rated cosmesis -- preservation of the normal appearance of the breast -- as good/excellent at two years, the relevant timepoint for evaluation of cosmesis.