A novel technique for treating deep seated breast cavity boosts.

Breast boost irradiation is an integral component to the standard of care for early staged breast cancer. The use of reduced tangents is common for deep seating tumor bed; however, reduced tangents result in non-conformal plans delivering prescription dose to large volumes of breast tissue. To improve conformity, a novel technique of integrating a single conformal arc with reduced tangents has been developed.

Dosimetric comparison of VMAT with integrated skin flash to 3D field-in-field tangents for left breast irradiation.

Volumetric modulated arc therapy (VMAT) has been implemented for left breast irradiation to reduce prescription dose to the heart and improve dose homogeneity across the targeted breast. Our in-house method requires application of a bolus during the optimization process with a target outside of the body, then removing the bolus during the final calculation in order to incorporate skin flash in VMAT plans. To quantify the dosimetric trade-offs between traditional 3D field-in-field tangents and VMAT with integrated skin flash for these patients, we compared nine consecutive patients who recently received radiation to their entire left breast but not their regional lymphatics.