If you're getting divorced, the standard fare is:

Lawyer up. Delete Facebook. Hit the gym.

If you've been given a potential cancer diagnosis, it isn't much different:

Doctor up. Delete Facebook. Hit the gym.

Doctor up.

The first step is getting a confirmed diagnosis from the first doctor that reads: cancer. Until you hear the word biopsy, its all speculation. It might be an educated guess, but again, speculation.

After you have your 'confirmed' diagnosis, GET A SECOND OPINION. Seriously, do it. It might cost you a little money, but it is well worth it. You'll want a different doctor in a different hospital system to diagnose it again. Do not leave anything to chance with something like this.

Delete Facebook.

This is going to be an emotionally trying time at the very best. It might not be something that you want to be broadcast via Facebook for all comers to see. That is definitely true if you reach a low point and post something you later deeply regret then can't take back. Cancer is more than people think it is.

Hit the gym.

The best defense is a good offense. A strong body deals with treatment better. Exercise, eat the most 'superfoods' and such as you can, and drink much more water. You want to essentially become one of those health focused nutcases that pushes it to the limit. You'll need every advantage you can get for her. It might also be a good idea to look into THC oil (plug for /r/trees) due to the anti-cancer properties. Google is your friend.

tl;dr At this point, you really don't know anything at all. The test hasn't confirmed anything except the need for more tests.