Editing GIST (section)

== '''Chemotherapy''' ==

* Neoadjuvant
** Indications:
*** Locally advanced tumours       such that multi-visceral resection would be required
*** Non-metastatic but       borderline resectable disease
*** Limited metastatic disease       which might be resectable, to assess response
** Can be continued up until      the time of surgery
* Adjuvant
** Indications:
*** High-risk pathological       features on resection (see below)
*** Tumour spillage during       resection
** Approach:
*** Risk-stratify with AFIP
*** Consider molecular       genotyping to better characterise response to imatinib
**** Worse response in KIT exon        9 mutation, PDGFRA exon 18 mutation, and KIT/PDGFRA wild type)
*** Intermediate or high-risk:       imatinib three years
*** No, very low or low-risk       GIST: surveillance
** Imatinib (Gleevec) 400-800mg      PO daily (tyrosine kinase inhibitor that blocks the unregulated c-kit      tyrosine kinase)
*** Works best if a mutation in       KIT is present, but some patients with wild type KIT are still       sensitive, due to the similarities between KIT and PDGFR-alpha
*** 400mg normally, 400mg BD if       Exon 9 mutation is present
** Second-line - sunitinib or      regorafenib
** 3 years is the current      standard of care
** 3 years vs 5 years currently      being investigated, trial completion date 2028
* Palliative