SUNNYVALE, Calif., Jan. 19, 2021 /PRNewswire/ -- Accuray Incorporated (NASDAQ: ARAY) announced today that data from a prospective, phase II trial of 338 women with low-risk breast cancer showed 98.8 percent 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.
"Over the last 10 years, breast-conserving surgery and APBI have been widely used in clinical practice for the treatment of low-risk breast cancer. Our large phase 2 trial demonstrated that IG-IMRT delivered using the TomoTherapy System offers improvements over existing techniques and can provide better APBI outcomes in carefully selected patient populations. The system enabled our team to increase the conformality and homogeneity of the dose to the tumor bed and reduce the dose to surrounding healthy tissue, making APBI an effective and convenient option for our patients," said Prof. Ugo de Paula, Department of Radiation Oncology, San Giovanni-Addolorata Hospital, Rome, Italy.
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;
