At some unavoidable point during the course of a relationship with most patients, the fateful question will be asked, “How long do I have to live?” Should there be a genuine wish to know, an honest and compassionate reply is the least deserved.
I shall set aside the point that at least three in ten of our cancer patients will be successfully cured of their cancer – thus for whom a Singapore life expectancy table dated 2/08 hopefully holds the answer. The remaining seven ask a question that is strangely difficult to answer truthfully to their satisfaction. We flounder between the uncertainty of statistical certainty, or the certainty of an individualized uncertainty.
“If a man will begin with certainties, he shall end in doubts: but if he will be content to begin with doubts, he shall end in certainties.”
— Francis Bacon.
A median survival is a strangely addictive answer for those among us who crave numerical certainty. Yet the median survival is only just that, a line carved out in the dirt dividing the taller half of the class from the shorter. Stephen Jay Gould famously wrote, “The median is not the message“. He would know, having outlived his median survival of eight months (with a diagnosis of mesothelioma) by some twenty years! Yet for every eminent Professor Gould, there is certainly one less fortunate and doubtless less vocal mesothelioma patient who would survive far less than eight months. So one must ask to whom I am doing a favour to in conveying a median survival of eight months. In any case, I always hope (perhaps unreasonably) that my patients are on the right side of the median!
An individualized prognosis by an oncologist (“based on your experience, doc…”) may seem a correct prescription. Unfortunately, when our crystal ball gazing abilities were actually put to the test, we cancer physicians didn’t do too well either. Specifically, almost one in two prognoses by experienced oncologists were reportedly off the mark. Worse, increasing professional experience did not correlate with better predictions so I don’t have anything to look forward to with the passage of time!
So it’s a difficult choice – living up the infallibility ascribed to physicians, or to offer only the vaguest of predictions, with assorted bromides?
“Hope never abandons you, you abandon it.” – George Weinberg.
And that brings us to the next topic for another day.
June 22, 2008 at 1:47 pm
[...] In my experience, however, patients hang on to their doctor’s words, and discussions centring around median survivals will result in patients concluding (erroneously in many situations) that Drug X will prolong their lives by several months, and that they are destined to live 20 months. This will be true for some, but untrue for many, many more. The median is not the message! [...]