ASCO Breast: Radiation Boost for DCIS Challenged, Proponents Unmoved

September 11, 2007

SAN FRANCISCO, Sept. 11 -- A retrospective study has cast doubt on the role of "boost" radiation therapy for ductal carcinoma in situ (DCIS), although the practice is likely to continue, researchers said.

SAN FRANCISCO, Sept. 11 -- A retrospective study has cast doubt on the role of "boost" radiation therapy for ductal carcinoma in situ (DCIS), although the practice is likely to continue, researchers said.

An optional radiation boost after lumpectomy for ductal carcinoma did not improve ipsilateral breast tumor recurrence rates overall (P=0.69) or for any subgroup of patients in retrospective analysis of a larger tamoxifen (Nolvadex) trial reported here at the American Society of Clinical Oncology Breast Cancer Symposium.

These findings contradicted those of a large randomized invasive breast cancer trial by the European Organization for Research and Treatment of Cancer (EORTC) that provided the rationale for testing boost in ductal carcinoma in situ, said Thomas B. Julian, M.D., of Drexel University in Philadelphia.

The results also sparked a debate from the floor.

"I don't think this retrospective data really should or will influence radiation oncologists' use of boost," commented Jay R. Harris, M.D., of the Dana-Farber Cancer Institute in Boston.

"Radiation oncologists are, of course, very influenced by the EORTC trial, which specifically looked at this boost question in 5,000 invasive cancer patients with very clear benefits [a 4% reduction in 10-year local recurrence, P