Just a quick note - medians and means can be very different, enough to cover 6 years (although I don't know whether UK uses the mean, so it may not be the reason for the difference between UK and US).
E.g. 11 patients, death ages: 3,6,9,15,20,36,39,45,54,55,56
Mean = 30.7, Median = 36
Obviously...