I find myself rather short of inspiration this morning. I realised I have not posted on this blog for a while so thought it was time to put something out there. After all, I have started experiencing people equating silence with probable death or incapacity. I met somebody in the street the other day. We were chatting away in a rather strained manner when after a couple of minutes she paused before rather ruefully sharing “you know, I thought you were dead”. I laughed and succeeded in removing any embarrassment, because I could fully understand her train of thought. She had no doubt seen my name on a prayer list and heard about my cancer somehow, but then heard nothing else for some months afterwards.
It is not unnatural to draw a morbid conclusion. I expect there are many others wandering the streets ready to be surprised in the same way. So at least I owe some regularity of posting for those that dip into my blog. I suppose it is a bit like climbing onto the roof of our apartment building once per month and shouting “I’m still here!”
I find it to be a good thing to be running out of inspiration for writing about a cancer journey, because it shows that the journey must be in a somewhat monotonous phase. In this situation no news is certainly good news. My health is rather stable. I notice that fewer people treat me like an invalid these days. My wife does not try to stop me doing the chores anymore, and even forgets sometimes to remind me to send her frequent “still alive” updates when I am moving about. At one point last year I shared with my therapist that the context of cancer invaded “every waking thought”, and at the time that felt accurate. It can only be good that some of my thoughts are now liberated from that context.
Part of that liberation is to find the motivation top tackle longer term projects. A good example is learning Portuguese. Ever since we have had plans to live there I have had a goal of learning the language, and a few months before my diagnosis I found an excellent website and started devoting a few hours per week to study. In October 2022 that habit stopped with a thud. Why work on such a tough project when I wasn’t going to live to obtain any reward for my effort? But after nine months or so I found myself drawn back to the website, and now I am back at full speed. Perhaps I will not get much opportunity to hone my new skill in Portugal itself, but perhaps I will. The idea no longer seems so futile.
So it is refreshing to notice that “every waking thought” no longer seems to apply. But it would be dishonest to claim that I am going about my life as free as a bird, even while I am feeling well. I am still prone to weird outbursts of tearfulness, though these do come and go, and their causes vary between fear, awe and thankfulness. I also find myself prone to cancer related musing, often while lying in bed.
Inevitably, much of this musing is about the two big questions that I understand my oncologists to be reluctant to speculate about. “How long do I have?” and “How is it likely to develop?” are frequently in my head. I know there is no good answer to either question, and I generally succeed in not asking them, and also not to research them on google either. But that is not enough to stop my mind from going to those places.
I carry two statistics around in my head. One is that the median survival time after a glioma diagnosis is between twelve and eighteen months. The other is that the survival rate after five years is less than ten percent. I am pretty sure that these are both accurate and relevant. Sometimes I share them with people who make the opposite mistake to those who think I must be dead already. These well-meaning people speculate that I am fully cured or soon will be, and sometimes I can’t help myself from correcting them.
I am now quite close to powering through the benchmark in my first statistic, it being sixteen months since diagnosis. One musing that has bedevilled me lately is how the life expectancy changes over time. Having got to eighteen months, am I now especially likely to keel over at a moment’s notice? Or is my life expectancy now another twelve to eighteen months from here? Or perhaps even longer?
Of course it is really a dumb question, since every case really is different. I won’t annoy my oncologist by asking him to speculate. There are a million factors in play. The initial median obscures a host of factors, and any renewed estimate would as well. How am I feeling? How is the rest of my health, including my mental health? Did I ever smoke? Is my heart in good shape? How effective is the care I receive at home? Will the infection reappear? Are the other symptoms merely annoying side effects, or might one become life threatening?
Despite all this, I could not stop myself with coming up with a theory. My hypothesis is that, so long as I feel as well as I did at the time of diagnosis, my life expectancy is probably still about twelve to eighteen months. If I still feel this well twelve months from now, I can hope for another twelve to eighteen months after that. And so on.
Ever the mathematician, this model has aspects related to a distribution called Poisson, named after a fishy Frenchman. We learned about Poisson distributions at school. They are quite elegant and good for problem solving and embedding some calculus concepts.
The example my teachers at school used to explain Poisson was waiting for a bus or a subway. It only works in a busy city where at busy times the published timetable is rather meaningless, and so the busses (buses?) turn up at rather random intervals from each other. I experience this while waiting for the Q60 bus or E or F subway trains in the evening. No matter how long you have waited already, the expected time until a bus arrives remains the same, always starting from now. If the average waiting time upon arrival at the stop was four minutes, you can still expect to wait four more minutes on average fifteen minutes later, whether no bus or six busses have passed in the interim. That is one of many interesting features of a Poisson distribution.
Might Monsieur Poisson have something to say about my current life expectancy (and by the way, everybody else’s too)? I suspect that he might. The features of a developing cancer will indeed follow some sort of independent pattern, like a phalanx of busses. I can even incorporate my second statistic, since a Poisson distribution with a mean (or is it median? I think it might be both) of fifteen months would indeed offer a probability of something less than ten percent of surviving five years or longer. But I can reset that five year probability now as well, starting from today. And I can again next month, so long as nothing else in my condition has changed.
I suppose this all rather pointless, even if my theory has some validity. But I share it as an example of the sort of musing that goes through the head of somebody with a condition like mine, perhaps while waiting for a bus. It is rather good for morale to be able to continually reset the mental clock, and to give some justification to such thoughts via reference to a fishy Frenchman.
And, pointless and even dumb as it is, such musings are probably rather more meaningful than clambering onto the roof to shout that I am not yet dead. Or cured.
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