Snapshot quiz 19/4
Authors: Ali N and Farooq TA
This large antimesenteric tumour in the proximal jejunum was treated by small bowel resection and anastomosis. The histological features and immunological profile were consistent with a gastrointestinal stromal tumour (GIST). The tumour was 78 mm in diameter, and the mitotic count was less than 5 per 50 high-power fields, which puts this tumour into the intermediate-risk category. GIST mutation analysis revealed a short deletion in KIT exon 11 as follows: c.1669_1674delp. (Trp557_Lys558del). The presence of a KIT mutation should be associated with sensitivity to imatinib treatment.