Since I already had a major bald spot (okay the entire top and back of my head), hair thinning was not an issue for me. No Cis just Erbitux and lots of Rad, but my neck and face became so sensitive that I could not shave so I ended up with a beard that fell out patch by patch with the dead and dying skin. A year out, same story as David on shaving -only need to above the chin, my neck is perfectly smooth. Back of neck hair making an appearance very slowly. I did daily lymph node massages and steam room visits to make the turkey neck go away quickly.
As everyone notes on OCF, radiation is the gift that keeps giving.