In breast cancer patients, helical TomoTherapy is not a suitable option since the gantry continuously rotates around the patient, and this technique can deliver low dose radiation to lungs that is associated with an occurrence of radiation pneumonitis. To avoid this inefficiency of beam usage, a TomoDirect option using static gantry positions combined with simultaneous couch translation and dynamic collimator modulation has been developed. In a pilot study, TomoDirect seemed particularly well suited for postoperative irradiation in breast cancer patients. TomoDirect achieved an optimal target volume coverage and coincident adequate normal tissue sparing in a dosimetric study. Clinical studies of TomoDirect in breast cancer patients are scarce and have been assessed only in small and retrospective series. Thus, we undertook a prospective study on the technical feasibility and toxicity of TomoDirect in breast cancer patients who received postoperative radiotherapy.
