Suppose one wanted to do survival analysis on any of the variety of data available through ICGC/TCGA.

Looking through the clinical information, I notice that in many cases the "specimen interval" (time interval from primary diagnosis to sample collection) is longer than the donor survival time (time interval from primary diagnosis to death).

This seems nonsensical as it implies that specimens were collected after the death of the donor... sometimes up to ~3000 days longer.

Any help untangling this would be very appreciated.