The treatment absolutely has a lasting impact - often due to the severe side effects of treatment. But even with notable impacts to short term memory and deep concentration I was still able to get a CS degree and work as a SWE.
Something that's shocking to me: the chronic absenteeism rate nationally is about 30%. I barely hit the threshold for that (missing 10% of school) number while going through cancer treatment. It makes me very worried about the direction of the US that so many kids are missing as much school a cancer patient.
It should also be noted that the treatment process is a big burden on families, who will probably not want their child be alone for extended hospital stays, but may need to for work.