So sorry to hear your story. Cancer just plan old sucks. It has impacted my family and one of my adopted children. My mom had pancreatic cancer (The deadliest of cancers) in 2017 and she is absolutely fine and cancer free a year later. Numbers don't mean anything to the individual and don't look them up is always my recommendation.
As a non-medically trained support member I have gotten pretty good in talking with the doctors about my family members cancers. I help explain them to others in my family and when I sit in the conversations with the doctors I stop them talking to make sure the patient is taking it in and understanding. I have unfortunately worked with many doctors and I have never had a negative experience with one when I stop them and ask the patient do you under stand and have them repeat what they heard. I even did this with my son when he was 8 because it was his body. I would than have a notebook and have them write down their questions throughout the day for when the doctors showed up (Usually around 6 or 7 AM)
I encourage everyone that enters the cancer world, as either a parent, spouse or close friend, to learn everything they can. The more you learn the madder I get at cancer research and specifically about pediatric cancer research. There is a Radio Lab Podcast and it got pretty intense for me to listen but I also understood cancer at a much better concise way after listening to this and specifically how cancer spreads. http://www.radiolab.org/story/91714-devil-tumors/
Three piece of information I always give to everyone:
1) The most important staff member of any doctor or surgeon is the Nurse Practitioner. They are the Master Sargent of that practice. Get their contact information and always make sure they are informed of what is happening.
2) Never assume that the different doctors are communicating, because 90% of the time they don't. Not between the surgeon and oncologist and even residents to other residents. Always ask question to make sure they know what is happening to you. Your the one making sure the different silos are talking.
3) Have two people you can call if you have any concerns. You get a gut feeling you don't ignore it. Doctors miss things all the time and you call that person that you trust. My mom started coughing after surgery and I knew it was serious. Two doctors from the surgeon's team show up and basically don't think it is serious. In the room I calmly said that we both have concerns and think someone else needs to see this. They were figuring out someone else to come to look at her. In the mean time I walked out of the room and called the surgeons nurse practitioner directly and state that I thought my mom's vocal cords were paralyzed, which I already ask the two doctors if they thought that was the issue. We were in the ICU within 10 minutes after that call and we were there for 4 days. My mom's voice came back 2 weeks later, she is a license counselor and her voice is her job. The thing is have a plan on who you can call if you get scared about something.