Hi,
Partial breast radiation (of which MammoSite is one brand) is increasing in popularity, but it is more expensive, and according to a 2010 article in the Journal of Clinical
Oncology, there has not been definitve reasearch showing that it is as effective as whole-
breast radiation treatments. Here is an excerpt:
Although the idea is promising, Sher said, there aren't any large studies that have compared whole-breast radiation to this treatment.