What is accelerated partial breast irradiation?

Traditionally, radiation therapy, following lumpectomy lasts for about 3-6 weeks. Under certain situations, however, patients may be eligible for shorter treatment durations. Treating simply the lumpectomy 'bed' rather than the entire breast, can be accomplished in 5 days or less.

Conventionally, radiation after a lumpectomy, is given over a 3-6 week period (16-33 treatments). Most of the ‘local recurrences’ of breast cancer, occur in and around the lumpectomy bed. So, the question was raised, are there circumstances, whereby only the lumpectomy bed be radiated? Indeed, that is was APBI (accelerated partial breast radiation) provides.