Figure 1. 3D reconstruction of the tumor and skull of the patient in the computer program Mimics. The tumor is marked pink. A)-C) Transparent skull seen from the front and from the right side. D) Opaque skull seen from behind. E) Computed tomography in frontal, axial and coronal plane and 3D reconstruction of opaque skull and tumor.

Figure 2. Haemotoxylin and eosin  staining  on tissue  samples from the first operation. Examination reveals tumor growth with elongated spindle like cells with small oval nuclei. The tissue has both high and low cell density areas but there is no visable atypia in tumor cells. No clear vascular structures are seen.  Many inflammatory cells are seen, numerus histiocytes but also lymphocytes and plasmacells. The image magnification is 10x, 20x and 40x.

Figure 3. Tumor cells show a mixed epithelial and mesenchymal phenotype. A og B) Cells growing out a tumor organoid show spindle like mesenchymal phenotype.  C) Immunofluorescence antibody staining for Vimentin (green) and A-smooth muscle actin/SMA (red) show both relations to fibroblasts (Vimentin) and myofibroblasts (SMA). This phenotype is very common in inflammatory myofibroblastic tumor cells. D and E) Antibody staining for N – and E – cadherin. F) The tumor cells also express the epithelial marker Cytokeratin 17.

Figure 4. Low attachment culture and antibody staining. These culturing conditions induce the growth of cells with stem cell properties. After low attachment culture cells express N-cadherin, Vimentin and Thy-1 but do not express smooth muscle actin (SMA), E-cadherin or cytokeratin 17.