I'm not sure Hendriks will necessarily miss most of the season. Obviously, the length of his recovery is somewhat uncertain but back in 1993, Mario Lemieux missed about 2 months of play undergoing treatment for the same disease. Obviously each person's timeline is different but if Hendriks started getting treatment already, maybe he won't be out too long. Best of luck to him.
We will see. Hopefully he can get cancer free ASAP and anything else after that (baseball) is gravy.