(HealthDay News) — Long-term follow-up of the START (Standardization of Breast Radiotherapy) trials confirms that appropriately-dosed hypofractionated radiotherapy is safe and effective for the treatment of invasive early breast cancer, according to research published online Sept. 19 in The Lancet Oncology.
Joanne S. Haviland, of the Institute of Cancer Research in Sutton, U.K., and colleagues report the results from 10 years of follow-up of trials that randomly assigned women with completely excised invasive breast cancer to 41.6 Gy or 39 Gy in 13 fractions over five weeks versus 50 Gy in 25 fractions over five weeks (START-A) or 40 Gy in 15 fractions over three weeks versus 50 Gy in 25 fractions over five weeks (START-B).
The researchers found that 10-year rates of local-regional relapse did not differ significantly between the groups in either trial. In START-A, fewer patients in the 39 Gy group had moderate or marked breast induration, telangiectasia, or breast edema compared to those in the 50 Gy group. In START-B, fewer patients in the 40 Gy group had breast shrinkage, telangiectasia, or breast edema compared to those in the 50 Gy group.
“The results support the continued use of 40 Gy in 15 fractions, which has already been adopted by most U.K. centers as the standard of care for women requiring adjuvant radiotherapy for invasive early breast cancer,” the authors write.