Please read and respond..Stomach and bone cancer

rbcxsoo500

Hi. My name is Soo. My best friend found out he had stomach cancer about 6 months ago. He is only 19. Y does it seem like he is the youngest guy to ever get stomach cancer? Anyways, my question is to anyone who can relate to him.
He got surgery and removed 3/4 of his cancer in his stomach. But a couple of days ago, he found out that the cancer spread to the bone for legs, spine, and ribs. Please tell me what this means. How bad is this? If anyone has statistics on the survival percentage, etc., please tell me.
I also found out that he is in stage 4 of cancer. I don't know anything about cancer. Please tell me what this means.
PLEASE!!! anyone that has gone through this or knows about this, please tell me. I really want to know if he has a good chance or not. I feel like I should prepare myself for what is to come.

Please, anyone, please.. I beg you to respond. This friend is too important to me. Thank you..

Soo