Three-week course of breast radiation
may be as effective as conventional five to seven week course for early breast
cancers
According to a study presented at the 51 Annual Meeting
of the American Society for Radiation Oncology (ASTRO), a shortened, more intensive
course of radiation given to the whole breast, along with a concomitant boost,
has been shown to result in excellent local control at a median follow up of two
years after treatment with no significant sides effects.
"The observations to date suggest that a three-week course
of radiation therapy with concomitant boost results in outcomes comparable to
that of a five to seven week course for early stage-breast cancers. Additional
studies with a larger body of data and longer follow-up period will help establish
whether this type of radiation treatment should be routinely used," Manjeet Chadha,
M.D., lead author of the study and a radiation oncologist at the Beth Israel Medical
Center in New York said.
This shorter treatment, called accelerated hypofractionated
whole breast irradiation, is an especially attractive option because women can
receive a full course of radiation therapy in half the time - three weeks of daily
treatments vs. five to seven weeks. In addition, the cost of this treatment is
lower relative to the cost of the standard whole breast radiation and is also
less expensive than other new approaches, such as breast brachytherapy.
"Studies from Europe and Canada have used accelerated
schedules for breast radiation therapy with favorable results reported on longer
follow up. In the U.S., however, there is limited data on this topic," Dr. Chadha
said. "Additionally, the radiation therapy technique used in our study is different
from previously published experiences. For each patient, we developed a conformal,
personalized plan using three-dimensional 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."
Beginning in June 2004, researchers studied 112 women
with early-stage breast cancer who received accelerated hypofractionated whole
breast irradiation plus concomitant boost. The results were reported on 105 patients
who had completed therapy and had a minimum six-month follow up. The patient group
had small breast tumors that had not spread to the lymph nodes. Women with early-stage
breast cancer who received chemotherapy or underwent radiation to the lymph nodes
were excluded from the study. Patients were followed at regular intervals after
completion of treatment.
Findings show that the cancer did not return to the original
site or to the surrounding region in these women. The median follow-up of the
study was two years. Survival was greater than 95 percent for patients with five
years of follow up. The study also shows there were no significant physical or
cosmetic side effects from the radiation treatment.
In an era of personalized care, Dr. Chadha emphasizes,
"Women with early-stage breast cancer interested in this shorter course should
ask their radiation oncologists about this option to evaluate whether it is suitable
for their individual case."
|