Fig. 3.

a, b Techniques for precise and feasible radiation dose delivery to the “hypoxic“ tumor segment while sparing the peri-tumoral-surrounding immune microenvironment: figure shows how a desired high radiation dose (red ring) is delivered by the mean of dynamic arcs (a) or multiple static radiation fields (b) very precisely and conformally to the hypoxic tumor segment (black area). Moving from that high-dose region through the normoxic tumor towards outside of the tumor, the dose will sharply fall off (orange ring-moderate dose, yellow ring-low dose) reaching an acceptably low dose-level (blue ring in a, or volume delineated by the blue lines in b) outside the tumor at the level of the tumor microenvironment. In this case, an acceptably low radiation dose will cover a small volume of the peri-tumor microenvironment closer to the tumor’s periphery leaving it intact and functional