okay so I had a talk with a doc friend who explained a bit more. the lymph node is located near some major artery called the SVC, meaning it's way too risky to remove it. we expected some would remain (the tumor marker wasn't zero) but with the active node in such a dangerous location, chemo will be needed after the surgery to get rid of it. I have no idea what type of chemo, for how long, any of that, and my oncologist never replied so I won't find out till Monday.
in addition, this surgery is apparently a tricky one, so if any of you have doctor parents, ask them if they know where the best mediastinal surgeons are in the country; I'm already doing this but it can't hurt to get a list of names or places.
That's a vein: Superior Vena Cava is probably the largest vein in the body and it basically carries all the blood from above your heart(Arms, head, brain) into it and yeah, I can see why a surgery there might be really delicate.
Now dude, don't rely on odds, really... Just stick to your desire to live. When my father was diagnosed with lymphoma the oncologist told us... "Prepare and say your goobyes, he's got three months at best."
But now it's been pretty much 4 years and albeit quite a few sequels (Mostly because it was BRAIN cancer), he's still kicking.