I had nasopharyngeal carcinoma treatment in 2006 - 35 sessions of radiation plus chemo as well. A few years after treatment, I thought I was back to norm!!
But in mid 2020 - when I started having issues with speech and swallowing (not to mention hearing impairments at the very beginning of treatment) - I was diagnosed with 'late effects of radiation'. And since then, 'late effects of radiation' creeps up bit by bit - numbness in lower jaw and lip, misaligned vision in left eye (radiation was on the left side), drooling, swallowing is getting worse - to the point where the last few drops will stay in my mouth - choice is to have a paper napkin to remove the excess or spit it out.
I believe these late effects apply to head and neck radiation treatment.
This is my personal journey .. and with advance in treatment - hope you fare better!!