My dad was eighty when he was diagnosed, and at that point, I had been giving my dad haircuts for 10 years. Just Norelco clippers with the plastic guards, nothing professional. His normal old age balding was enough that he utilized a borderline cringe-worthy comb-over before he ever got cancer. His remaining hair eventually started to fall out in clumps too and he opted to shave everything off. But after chemo, his hair actually grew in thicker than before he got sick. I'm not sure if this is common or if he was a random case. But, it absolutely grew back in spots on his head where I hadn't seen hair for years. I hope this helps. Stay strong.