An abridged, intensified radiation course proved to be as effective as the standard five- to seven-week treatment in early-stage breast cancer patients, based on results of a study presented Wednesday at the 2009 American Society for Radiation Oncology (ASTRO) conference in Chicago.
"The observations to date suggest that a three-week course of radiation therapy with concomitant boost results in outcomes comparable with that of a five- to seven-week course for early-stage breast cancers," said the study’s lead author, Manjeet Chadha, MD, a radiation oncologist at the Beth Israel Medical Center in New York City.
With standard breast radiation treatment, patients receive treatments every Monday through Friday—15 to 30 minutes per day—for five- to seven-week weeks. The shorter, hypofractionated whole-breast irradiation in this trial is completed in just three weeks, researchers said.
Researchers studied the hypofractionated whole-breast irradiation, with an added dose of radiation to the tumor’s surgical bed (concomitant boost) on 112 patients in the early stages of breast cancer.
Of 105 patients who completed the therapy with a six-month follow-up, results showed cancer to be absent in the original or surrounding regions of the breast after treatment. Researchers recorded that those patients who had follow ups for five years had a 95 percent survival rate and no notable physical or cosmetic side effects after treatments.
“We developed a conformal, personalized plan using 3D dosimetry data derived from the patient specific CT scan images. Radiation treatment was delivered to the whole breast using an accelerated hypofractionated schedule, with the simultaneous delivery of a boost dose given to the precise location from which the tumor was removed," Chadha said.
Patients whose early-stage cancer had infiltrated the lymph nodes were excluded from the study.
In addition, the hypofractionated treatment, according to researchers, proved to cost less than that of the standard five- to seven-week treatment and less than other methods such as breast brachytherapy.
According to Chadha, the United States has produced limited data on this particular topic compared with studies carried out in Europe and Canada that showed favorable results after radiation therapy.
“Additional studies with a larger body of data and a longer follow-up period will help establish whether this type of radiation treatment should be routinely used," Chadha said.