Do what YOU need to do for YOU. He has been told he needs a biopsy, THAT IS NOT A DECLARATION OF CANCER. It is simply 1 of a number of tests to see what is happening, BEFORE a diagnosis is give. But trust an A to hit the drama button and yell "help", before he knows anything is actually wrong.
Well, you saw he had a drinking problem and asked him to sort it, but he did nothing and you did what you had to do then, left him. He is still drinking, and the only change is his idea that he now has CANCER, but obviously NOT in a hurry to have the biopsy. Hmmmm!
I would let it continue as is, at least until you have proof of a definite diagnosis and then see what YOU want to do.
May I suggest that if someone chides you about you not caring for your AH, you tell them to go care for him, walk in your shoes and see how they cope with it all. Then tell them to butt out of your business.
Stay annoyed, if you can't manage angry....much healthier than sad.
God bless