Wishing for the Best for Koko!
If it is cancer - and I hope not - I can tell you what I did for C.B. He was 18 and had a tumor on his nose between his eyes. I chose to have him get radiation. I knew well that it wouldn't cure him, but it did eventually make him more comfortable and possibly extend his life. Yes, it was expensive and I had to travel a bit for it, but I had to do what seemed right for him. He was blind which they said could have come from the radiation treatments, but I think the tumor and age started his blindness. When his brother passed at the age of 19 without cancer, he was blind then, too. My heart goes out to you. I'm believe you'll do for Koko whatever feels right for him and for you.