You have to ask the radiation oncologist this to get an accurate answer because it depends on what exactly the radiation focus was, how long, total dose and time, focus of the beam, etc....
However, if the nerves to smell were damaged, there is only about a 50/50 chance that smell will come back.
And, that will take up to a year.
It is smell that is affecting the taste.....that is in most cases.
If it were only the nerves to taste...about the same risks and time line.
My over all take on this is that the rad/onc doc would have tailored the timing the dose as to not have permanently affected smell and hence taste. If this happened rather after surgery, that would be a different issue, with more damage likely.
OK, so that is an initial answer….
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