Boost radiotherapy  in addition to surgery for breast-conserving treatment for DCIS 

In the absence of a randomized trial and in analogy to the boost irradiation in young patients with invasive breast cancer our work will likely change clinical practice in a lot of centers, including our, in regard to the management of young patients with DCIS. Currently there are no sufficient data to select a probably 'good risk' situation among patients <45yrs, so in the absence of other data I would give a boost of 10-16Gy to younger patients in general, but exceptions might be possible, like in well differentiated small tumors with good resection margins. However, if you stress again the comparison with invasive cancer, one should probably give a boost in every
young woman as age itself represents a very strong prognostic factor, which is true in both, DCIS and invasive breast cancer.
The logical next step would be a randomized trial testing this hypothesis of boost radiotherapy, however doctors and patients might be of concern not to give a boost according to the quite convincing results of our study.

Bibliographical reference:

Omlin A et al.: "Boost radiotherapy in young women with ductal carcinoma in situ: a multicentre, retrospective study of the Rare Cancer Network", Lancet Oncology, Early Online Publication, 6 July 2006

Guenther Gruber

Institute of Radiation Oncology, Kantonsspital, Aarau, Switzerland