Postoperative radiotherapy after DCIS: Useful for whom?

Several factors in different trials have shown to influence the risk for an ipsilateral event: age, size, grade, necrosis, clear margin, and detected on mammography or not. But identification of subgroups without relative efficacy of radiotherapy has been challenging to find. The Van Nuys prognostic index and the nomogram from the Memorial Sloan-Kettering take several of these factors into account. These and genomic assays may help to optimize the treatments of patients with DCIS. Still, radiotherapy after breast conserving surgery is the standard of care for a majority of DCIS patients. For some low risk DCIS patients accepting a slight increased risk of an ipsilateral event it is reasonable to omit radiotherapy after close communication with the patient about pros and cons of radiotherapy.