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The EQD2 for the above regimen was estimated to be 45 Gy with a total of 60 Gy when the boost is included. In contrast to the randomized Chinese trial, they used primarily photons and 3D-planning. Goal chest wall coverage was at least 90% of prescription with a maximum dose of 115%. The RTOG chest wall and nodal volumes were not utilized in planning, but a random evaluation of target coverage showed that D95% for the chest wall and axilla was 97% and 92% of prescription, respectively, on average. The main volumetric constraint was brachial plexus max dose of 39.2 Gy (107%). The heart was blocked as much as possible and tangent depth into the lung was ideally < 3 cm, but volume-based planning and optimization was limited.  In retrospect, this led to a mean heart dose of just 1.3 Gy (range 0.3 to 3.8 Gy), a heart V20 of 0.3%, and an ipsilateral lung V15 (felt to be equivalent to conventional V20) of 24.8%. TBL: While this trial used conventional planning techniques and a unique dose schedule, look for more volume-based planning and a more “conventional” 42.56 Gy in 16 fractions from RT CHARM. | Poppe, Int J Radiat Oncol Biol Phys 2020