There are a number of different types of statistics used surrounding cancer, but one of the most frequently used is a type of average called the median.
Statistics are important and helpful, but they still don't allow us to predict how an individual patient will do.
Recently a friend and colleague directed us to this beautiful essay by one of the great thinkers of our time, the evolutionary biologist Stephen Jay Gould. It relates to his personal experience with cancer, and different ways of interpreting the survival data that patients and doctors have available to them.
We find it to be very helpful to remember that a specific number does not tell you how an individual patient will do with or without therapy; there are always “outliers”. In addition, there are many treatments that do not change the median survival because the advantage is to fewer than half of the patients. The benefit for those individuals, of course, is great.