Primary gastrointestinal stromal tumor of the liver treated with sequential therapy

Figure 1 Computed tomography images of the tumor. A: An enhanced abdominal computed tomography (CT) scan from August 2009 showed a 7.4 cm × 6.2 cm solid-cystic mass in the right hepatic lobe (venous phases in the axial plane). The central portion was of low-density with thickened irregular peripheral margins; B: An enhanced abdominal CT scan in September 2011 showed a 6 cm × 5 cm solid-cystic mass in the residual right liver (venous phases in the axial plane).

Figure 2 Microscopic and immunohistochemical findings of the resected specimen obtained in August 2009. A: Microscopically, the tumor was composed of spindle cells and epithelioid cells with high mitotic activity (8/50 HPF) (hematoxylin-eosin, original magnification × 400); B, C: Immunohistochemical staining with antibodies against CD117 (B) and CD34 (C) showed diffuse cytoplasmic staining of almost all tumor cells when compared with the lack of staining in adjacent liver tissue (original magnification × 400).