Shorter regimen of radiotherapy safe for noninvasive breast cancer patients

Treatment time for this common cancer could be cut in half

Accelerated whole breast irradiation after lumpectomy is an effective treatment for ductal carcinoma in situ (DCIS), a very common early stage and noninvasive form of breast cancer, meaning many more breast cancer patients could see their treatment times reduced by half, according to a study in the June issue of the International Journal of Radiation Oncology-Biology-Physics, the official scientific journal of the American Society for Radiation Oncology (ASTRO).

The widespread use of mammography beginning in the early 1980s has led to a dramatic increase in the number of DCIS instances detected, making this one of the most common forms of breast cancer. Multiple studies have proven that lumpectomy plus radiation significantly reduces the risk of recurrence in both noninvasive and invasive breast cancers and for DCIS, the current standard of treatment is lumpectomy followed by five to six weeks of whole breast radiation.

However, for invasive cancers, the use of an accelerated form of radiation that increases the strength of the dose per treatment and uses fewer treatment sessions overall has been well-established as effective, providing patients with a shorter treatment time with similar positive results. The effectiveness of an accelerated treatment time has not been established for DCIS.

Researchers in the study followed 145 DCIS patients who were treated with lumpectomy and accelerated whole breast irradiation or lumpectomy with accelerated whole breast irradiation plus an additional daily boost. At five years post-treatment, only 4.1 percent of patients experienced a recurrence, which is comparable to the five to 10 percent recurrence rate demonstrated in randomized trials for patients receiving standard radiation.

"The results of our study suggest that DCIS patients can be safely treated with a shorter regimen of radiotherapy," Silvia Formenti, MD, senior author of the study and a radiation oncologist at New York University School of Medicine, said. "This is good news for many breast cancer patients who would prefer to receive their treatments in a shorter period of time, but also want the peace of mind that they are receiving the most effective treatment available."