@edgarblythe,
I once had an apparently not so dastardly to me breast cancer (stage 2, almost ten years ago) but I lived then in a situation in a small town where I didn't want to deal with what I could project would be the How Are You well meant conversations, as that could just take over my days and life, when I was optimistic, which turned out to be smart. So I only told one person, my business partner. I suppose she told a few others in her family, but there was no buzz.
That meant that I was without the succor of community concern (picture me, if I had told, at gallery openings of several hundred people, explaining forever, instead of talking about the artist's work or just enjoying myself) - but I was relatively new in town and had a background of many years with good friends, albeit not in the area; one did travel and stay with me through the more scary surgery. I was able to do this since I didn't lose hair.
Some time around the same time, but somewhat later, we showed the work of a woman painter who went through more advanced stages and painted about it (I might have remarked on it on a2k), as did a former gallery owner partner of mine, many years before, who painted a huge painting about the yew plant before succumbing. I don't know how they would have felt re the question at any given time.
So, my view on this is - use the words 'how are you' if you mean them.
Never mind about heart surgery or cancer, just ordinary stuff.
Things ramify: people might want to tell, and struggle not to; people might need to tell, and are you there to listen?
I suppose though, that there are centuries behind 'how are you?' and 'fine', in many languages.
So we all - or at least in many places - deal with that.
