A friend of my aunt's made a quilt like this for her. I don't recall how big it was, I think maybe throw size. That way it could be brought to the hospital for treatment too. Then she had friends and family members sign it or write messages of encouragement. As others have said, I'd go with things the recipient likes, or happy cheerful colors, staying away from the traditional pink and so forth. I'd also go with materials that will wash well. I wonder if maybe flannel/minky for the back and just traditional cotton on the front so if she is feeling warmer or colder she will have a choice about which fabric she wants against her skin.