Imaging for early stage breast cancer

Intracavitary BT (ML MammoSite – Contura)

sources are far from target volume

4 - 5 channels – more dwell positions

sphere-like target volume and dose distribution

no geometric miss – tissue conformance is not always guaranteed (air gaps)

limited asymmetric margin

relatively homogeneous dose distribution

Kim et al. J Appl Clin Med Phys 15(1):4429. 2014

small dose gradient at target edge

modest dose modulation potential