Management of GIST

Mutational analysis involving KIT and PDGFRA can confirm diagnosis of GIST and isstandard practice in the diagnosis work up of all cases.PDGFRA D842V-mutated GIST are notsensitive to adjuvant imatinib and so should not receive it.In KIT/PDGFRA/BRAF wild-type GISTs, adjuvant treatment should be avoided inneurofibromatosis type 1-related and SDH expression-negative GISTs, which lack sensitivity toTKIs and also have more indolent nature. patients with tumor rupture at the time of surgery shouldbe considered for imatinib treatment.If RO surgery is not feasible pretreatment imatinib is recommended. patients with KIT exon9 mutations ,800 mg daily imatinib is recommended. Patients with PDGFRA mutation aregenerally insensitive to TKIs and are candidates for clinical trials and patients with wild-type SDHdeficient GISTs do not benefit from TKIs.A weeks on/2weeks off regimen is effective but acontinuously dosed daily oral regimen of 37.5 mg can be considered on an individual basis.Following progression on sunitinib regorafenib 160 mg daily for out of every weeks is thestandard third line approach.Data at ASCO 2018 demonstrated initial clinical benefit of DCC2618with encouraging ORR and DCR in 2nd ,3rd,> 4th line GIST patients.