If you didn’t read carefully yesterday’s QuadShot about post-mastectomy hypofractionation, you may have skimmed over the fact that radiation was delivered to the chest wall by a single electron field in most patients. Having never done it before, we assume there would be an en face electron beam angled such that the medial and lateral chest wall borders are equidistant from the central axis, where dose was prescribed to a maximum dose. For 6-MeV beams used without bolus, this would place 75-80% of dose at the surface, 90% beginning and ending around 1 and 2 cm, the max dose at 1.5cm, and the range at about 3 cm. Such an approach is a major departure from techniques most in the US are accustomed to using. Seeing these plans superimposed on modern target volumes would be interesting to say the least, especially considering the relatively low rates of locoregional recurrences. TBL: Thinking through these details highlights why this thought-provoking data will ultimately need a Western trial to confirm its application with traditional fields. | Wang, Lancet Oncol 2019


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