Molecular basis and management of gastrointestinal stromal tumors

Table 3 Prevalence of c-kit and PDGFR-A mutations and clinical responses in advanced GISTs to imatinib and sunitinib correlated with mutational status

Genotype	Prevalence[59-61]	Clinical benefit from imatinib[15,58,59]	Clinical benefit from sunitinib[581
KIT exon 9 mutation (%)	5-14	74-81	60
KIT exon 11 mutation (%)	57-69	83-93	35
KIT exon 13 mutation (%)	< 5	60-100 (few cases)	65
KIT exon 17 mutation (%)	< 5	75-80 (few cases)
PDGFR-A mutations (%)	3-8	40-66	0 (few cases)
Both wild-type (%)	5-10	33-73	55

Clinical benefit is defined as complete, partial response or stable disease. ¹In imatinib-resistant GIST.