They can dose paint. Check your cumulative dose volume histogram on your treatment plan, if you have it. I don't know if they do 53Gy to the parotid gland with IMRT, and read, they can spare, do lesser radistion due to the limited dose toxicity of 30Gy, but anything is possible. Mine looks like it started at 28Gy, but the histogram is somewhat difficult to figure out with the cGy, ratio of total structure volume%, and relative dose%. They also do lesser radiation than the primary for the right and left brachial plexus nerve, like 53Gy, brain stem 53Gy, larynx 35Gy, spinal cord 15Gy, and mandible 34Gy due to toxicity levels. I was turned down for radiation 2x, for two recurrences in level V, due to already receiving the max radiation to the left brachial plexus nerve, which area originally was given 53Gy-66Gy depending on the proximity to level lV. Check with the Wizard of Oz. lol.