Consider Re-simulation or Evaluate With and Without Density Overrides

To start with, we would not have any portion of the gross tumor volume/clinical target volume in-air, although that will make little difference in this case (1). This is a complicated case; the best option maybe to re-simulate with wet gauze around the area, to reduce dosimetric uncertainties in the build-up region as well as to enable traditional handling of the planning target volume (PTV), without the computer needing to give dose to air. If this is not acceptable, the plan could be optimized with the PTV "as-is" and then recomputed, not reoptimitzed, with the PTV set to a density of tissue and the difference between the 2 plans evaluated.

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