Imaging for early stage breast cancer

Validating fiducial markers for IGRT for APBI

- in 26 patients 3-4 gold fiducial markers placed at the periphery of lumpectomy cavity - free breathing 4D CTs were acquired pre- and posttreatment - intrafraction motion, variations in respiratory motion and fiducial migration were calculated

end-inspiration end-expiration

end-inspiration end-expiration

fiducial markers are stable throughout the course of APBI, no evidence of migration

planning target volume margins when using bony landmarks should be 10 mm and can be

reduced to 6 mm if using fiducials

Park et al. IJROBP 82:e425-e431. 2012