PUBLIC RELEASE DATE:

9-Dec-2014

Contact: Michelle Kirkwood press@astro.org 703-286-1600 American Society for Radiation Oncology @ASTRO_org

Fairfax, Va., December 9, 2014--The use of hypofractionated whole-breast irradiation (HF-WBI) for patients with early-stage breast cancer increased 17.4 percent from 2004 to 2011, and patients are more likely to receive HF-WBI compared to conventionally fractionated whole-breast irradiation (CF-WBI) when they are treated at an academic center or live 50 miles away from a cancer center, according to a study published in the December 1, 2014 issue of the International Journal of Radiation Oncology Biology Physics (Red Journal), the official scientific journal of the American Society for Radiation Oncology (ASTRO).

An analysis of randomized trials[1] demonstrated that patients with early-stage breast cancer who are treated with breast-conserving surgery and adjuvant whole-breast irradiation have improved survival and a lower risk of tumor recurrence compared to patients who are not treated with radiation therapy. Patients are commonly treated with CF-WBI; however, several recent randomized trials[2-5] have confirmed that patients treated with HF-WBI have similar disease-free and overall survival rates as those treated with CF-WBI. CF-WBI delivers a total dose of 45-50 Gy in 25-28 daily fractions of 1.8-2.0 Gy over five to six weeks, while HF-WBI uses a shorter treatment course and a lower total dose and number of fractions, delivering a total dose of 39-42.5 Gy in 13-16 daily fractions of 2.5-3.2 Gy over three to five weeks.

This study, "Adoption of Hypofractionated Whole-Breast Irradiation for Early-Stage Breast Cancer: A National Cancer Data Base Analysis," is a retrospective review of 113,267 early-stage breast cancer patients in the National Cancer Data Base (NCDB) from 2004 to 2011 who were treated with radiation therapy and were eligible to receive HF-WBI, and examines the use of HF-WBI compared to CF-WBI and the factors, including facility type and patient's distance from the radiation treatment center, that influenced which type of WBI the patient received.

The NCDB, a joint program of the American College of Surgeons' Commission on Cancer and the American Cancer Society established in 1989, is a nationwide, facility-based data set that contains retrospective data on 70 percent of all newly diagnosed cancers in the United States.

The study identified data from early-stage breast cancer patients included in the NDCB from 2004 to 2011 who received adjuvant WBI and who were eligible to receive HF-WBI according to current guidelines and randomized trials. Eligible patients were age 50 or older at the time of diagnosis; had a first and only diagnosis of breast cancer; had pathologic stage T1-2 N0 breast cancer, based on the American Joint Committee on Cancer TNM staging classification; were treated with breast-conserving surgery; and did not receive chemotherapy. In this study, HF-WBI was defined as a fraction dose of 2.2 Gy and 4.0 Gy, and CF-WBI was defined was a fraction dose >1.5 Gy and <2.2 Gy. Regional radiation therapy total dose was limited to 40-66.4 Gy, and boost doses were limited to <21.6 Gy.

Patients who received regional nodal radiation therapy; who received brachytherapy, stereotactic radiation therapy and treatments delivered with electron, neutron or proton beams; who received fewer than 10 or more than 50 fractions; or who received radiation therapy as palliative care were not included in the analysis.

The study identified 113,267 female, early-stage breast cancer patients who were eligible for analysis. Of those patients, 11.7 percent (13,271) received HF-WBI, and 88.3 percent (99,996) received CF-WBI. Based on the data used in this study, 5.4 percent (677) of patients treated in 2004 received HF-WBI compared to the 22.8 percent (3,809) of patients treated in 2011 who received HF-WBI. While the use of HF-WBI increased, the use of CF-WBI decreased; however, CF-WBI was still prescribed for a majority of patients, with 94.6 percent (11,735) of patients receiving CF-WBI in 2004 and 77.2 percent (12,876) of patients receiving CF-WBI in 2011.

Continued here:

Analysis shows increased use of HF-WBI for patients with early-stage breast cancer