KIT genotype also predicts duration of response to STI571.  The time to treatment failure data for patients is shown as % of patients with treatment failure vs time in days for the three largest genotypes in this study.  As shown here, the median time to treatment failure was 87 days for GISTs with no mutation, 230 days for GISTs with an exon 9 mutation and has not been reached for patients with an exon 11 mutation.  The difference in ttf for exon 11 vs no mutation or exon 9 GISTs had a p value of <0.00001.  There was no statistical difference in the TTF for exon 9 vs no mutation cases.