Yes, Dylan has Leukemia. Everyone in the industry knows, but its too serious of a subject for anyone to confirm on any media site/magazine. The only way it will be confirmed is if Dylan does it himself, which is how it should be. In the end its his battle and if he doesn't want to publicly disclose what is going on then no one else should do it for him.
Dylan has been going through chemo (obviously) and it appears that the Leukemia is in recession. Looks like a full recovery could happen, but it's up in the air if his skating will ever be the same. Who knows though, people have had miraculous recoveries before and being that he is still in his 20s, there's a good chance he can be back to his old self.
It will take at least another couple of years for him to be back to the old Dylan, as he still needs a some more treatments and assuming he is 100 percent cancer free, he would then have to rebuild his muscle and get comfortable on a board again, which will be the easiest part for him I am assuming.
Stop being disrespectful shits and saying dumb shit about a guy who has serious illness. Sure its fun to get everyone pissed off on the board, I get it, but seriously, fuck off with that immature bullshit. Show a fellow skater some support.