The latest suggested immunotherapy is called ``nivolumab'', or ``nivo'' for short. Both nivo and atezo are known as ``immune checkpoint inhibitors'', the difference being that nivo tries to block PD-1 (``death cells'') whereas atezo tries to block PDL-1 (``death cell ligands''). I originally thought the PD-1's were the good guys and the PDL-1's the bad guys, but apparently the game is just to prevent by whatever means necessary the linking of the PDL-1's (which are on the cancer cells) to the PD-1's (which are on the good cells). This frees the cavalry to charge out to the rescue and attack the cancer cells. Well, obviously I don't yet understand the biology here, but in any case such understanding only serves to satisfy intellectual curiosity---it doesn't help make the decision.
The one major study of nivo involved 275 patients. It had a somewhat higher ``objective response rate'' than the atezo study, although with such small sample sizes I doubt this is statistically significant. The side-effects are the same, with fatigue and colitis (diarrhea) being the most common. The colitis sounds like it can be bad enough to prevent you from doing much of anything. Supposedly it can be treated with steroids, which of course have their own nasty side-effects. Moreover the colitis doesn't necessarily go away when the treatment is stopped. Without meaning to be overly cynical, I will also mention that the nivo study was funded by Bristol-Squibb, the company that makes and sells the drug. All things considered, then, I am much less enthusiastic than the authors of the study about the prospects of nivo (or atezo).
I wish it were possible to get case studies. Was the typical patient a 98-year old chain-smoking alchoholic with a bad heart and a wooden leg? Or was it a robust young man in the prime of health like myself? I wish I could obtain individual reports or accounts written by the patients themselves. It's very hard to know what to make of the statistics, since the definitions of partial response, complete response and so on are so vague.
The oncologist favors atezo over nivo, because (a) the infusions are once every three weeks for the former and every two weeks for the latter, and (b) atezo is cheaper and therefore a better choice for the common good. Well, I certainly want to do my part for the common good, although I confess item (a) would be the deciding factor for me---assuming I go this route at all. Once again I asked him what he thought would be the likely outcome if I choose no therapy at all. After stressing that there is no such thing as a ``median patient'', he said the median survival would be six months. I knew this from the literature already, but wanted to hear it from him. Of course, as I've said before, I would be mortified to only reach the median; the sheer embarassment of croaking that quickly would motivate me to beat the odds.
The oncologist seemed okay with the idea that I wait for the next scan before deciding, although I think this is because he's given up on convincing me to play a conservative game. The fact is that I still don't know what I will do. No one can help me with this decision (and I must say I'm very grateful that no one---doctors, family, friends---has pressured me to do anything). It's all on me, as it should be. Despite that dire ``six months'' figure, one side of me wants to say screw it, I'm going to put off therapy indefinitely and keep focusing on enjoying life now. The colitis (says the doc) can mean ten or more diarrhea attacks a day, which would put a bit of a damper on enjoyment, or even functioning. I wouldn't mind risking this if I knew it could be stopped by stopping the therapy, but the thought of a permanent such condition is pretty repulsive. And how bad is the fatigue? This is the kind of information that's impossible to get. There are other side-effects too.
I take much inspiration from Tiziano Terzani. He eventually reached a point where he said enough is enough; I'm done with treatments, I'll enjoy life now and accept death when it comes. Now admittedly, Terzani pursued treatment options much more extensively than I have. He spent a lot of time at Sloan-Kettering in New York undergoing chemo and radio (ironically, our cab from JFK went right past Sloan-Kettering on the way to meet Abby), and then travelled the world experimenting with various ``Eastern'' and even New Age-y approaches. He didn't really believe in most of these; the trip was motivated also by journalistic curiosity and led to his book ``Another spin on the merry-go-round''. Terzani also had a much more highly developed personal philosophy than I do, based in part on his extensive studies of Hindu and Buddhist ideas. Nevertheless, in my own way, I feel a strong connection to his point of view.
Would I have been better off not interrupting my chemo to go to Italy? From the conservative point of view, i.e. of maximizing life-span at all costs, maybe yes. But I'm not going to do that. Would I have been better off starting immunotherapy last month, even if it rendered our New York trip impossible? Conservatively, maybe yes. But I am very, very glad that I didn't jeopardize the trip. We had a fantastic time visiting Abby and Oliver. I'm not going to forego living for the sake of living longer.
Maybe I should decide just how long I'm going to procrastinate. But not today. The sun is out, and life is wonderful!