Multiple malignant extragastrointestinal stromal tumors of the greater omentum and results of immunohistochemistry and mutation analysis: A case report

Figure 1 Homo-genous hypovascular hypo-echoic mass lesions in the mese-ntery on ultrasonography.

Figure 2 Lesions adjacent to small bowel loop in left abdomen and ill defined low density cystic change on computed tomography.

Figure 3 A: Gross findings of the specimen: two irregular fragments of omental tissue and several irregular fragments of soft tissue masses; B: Diffuse pale brownish flesh-like appearance with multiple hemorrhagic necrosis on cut surface.

Figure 4 A: The spindle cells showed cytoplasmic positive reactivity for CD 117 (c-kit) on immunohistochemical findings; B: Ki-67 labeling index was about 30%-40% on immuno-histochemical findings; C: The tumor was composed of spindle cells showing a less developed fascicular pattern on histologic findings (x 100); D: The tumor had a high mitotic activity, about 115/50 HPFs mitotic counts on histologic findings (x 400).

Figure 5 There was a heterozygote on exon 11, showing GTT (val. ) to GWT (val. + asp.) transition at codon 559 in c-kit mutation.

Figure 6 There was a polymorphism on exon 12, showing CAA (pro. ) to CCG (pro.) transition at codon 567 in mutation of PDGFRA.