How do I cope with learning that my Aunt has cancer?

I just found out my aunt has cancer! They found it during her historectomy but im not sure exactly wheree the cancer is. I love her alot and dont want her to die. What should I do to haandle this awful info I just recieved? I am very upset about this (obviously) and I have no idea what to think or if I should even be worried. How did you handle hearing you or a loved one has cancer? Is it ok to cry about it or how should I react?