In the absence of clear recommendations, a shorter duration, less costly type of radiation treatment among women with early-stage breast cancer who had breast conserving surgery is not being utilized among the patients who meet treatment guidelines, according to a study published Dec. 10 in the Journal of the American Medical Association.

A retrospective, cohort study was led by Justin E. Bekelman, MD, of the Hospital of the University of Pennsylvania, and colleagues and used claims data from 14 commercial health care plans covering more than 7 percent of the adult population in the U.S.

The study authors noted whole breast irradiation (WBI) is recommended for most women after breast conserving surgery. Conventional WBI lasts five to seven weeks and is composed of daily radiation treatment. Hypofractionated WBI is shorter in duration (usually just three weeks) and uses higher doses of radiation.

In an effort to determine the use of hypofractionated and conventional WBI and related costs, researchers categorized participants with early-stage breast cancer treated with lumpectomy and whole breast irradiation (WBI) from 2008 and 2013 into two cohorts:

• A hypofractionation-endorsed cohort of 8,924 patients aged 50 years or older without prior chemotherapy or axillary lymph node involvement; and
• A hypofractionation-permitted cohort of 6,719 patients aged 50 years and younger or those with prior chemotherapy or axillary lymph node involvement.

The researchers found that hypofractionation WBI increased from 10.6 percent in 2008 to 34.5 percent in 2013 in the hypofractioned-endorsed cohort and from 8.1 percent to 21.2 percent in the hyporfractionation–permitted cohort.

They found healthcare expenditures in the year after diagnosis were $28,747 for hypofractionated and $31,641 for conventional WBI in the hypofractionation-permitted group.

The authors concluded that hypofractionated WBI after breast conserving surgery increased among women with early-stage breast cancer in the studied commercial healthcare plans, but found that only 34.5 percent of women with the hypofractionation-endorsed and 21.2 percent with the hypofractionation-permitted cancers received hypofractionated WBI in 2013, despite it resulting in lower expenditure rates.

“The absence of a clear recommendation may have contributed to slower uptake of hypofractionation in the United States than in other countries,” the authors wrote. “In 2013, we observed more pronounced uptake of hypofractionation; evaluation of future treatment patterns will be important to document whether or not this trend reflects the beginning of more widespread adoption.”