Radiation Boosts DCIS Relapse-Free Survival in Women with Breast Cancer

July 6, 2006

BERN, Switzerland - Young women who have radiotherapy following surgery for ductal carcinoma in-situ (DCIS) are significantly less likely to have local recurrence and the risk was even lower when boost radiotherapy was added.

BERN, Switzerland, July 6 ? Radiotherapy following surgery for ductal carcinoma in-situ (DCIS) leads to a significantly lower risk of local recurrence, and the risk was even lower when boost radiotherapy was added.

Forty-six percent of young women who had surgical excision alone were relapse-free for 10 years, Aurelius Omlin, M.D., of the University of Bern, and colleagues, reported in Lancet Oncology, which was published online today.

But that rate jumped to 72% with radiation and to 86% for young women who had radiotherapy and an extra "boost" of radiation, said Dr. Bern and colleagues from 18 institutions in the United States and Europe.

The 10-year overall survival was 97% for all young women with no significant differences between the three treatment groups (P=0.96).

The authors pointed out that mammography screening has increased the number of DCIS diagnoses but "little is known about the best treatment in young patients with DCIS, who are a minority of the DCIS patients."

The investigators reviewed data from 373 women ages 45 or younger who were treated for DCIS from February 1978 through August 2004. Fifty-seven women had no radiation, 166 had surgery plus radiation (median dose 50 Gy), and 150 women had radiotherapy with boost (median dose 60 Gy).

"Compared with no radiotherapy, radiotherapy without boost was associated with a reduced risk of local relapse (P=0.004), as was radiotherapy with boost (P