Gross and histological findings. A. The resected fresh specimen showed dark yellowish soft tumor, measuring 31 mm in diameter, with no capsule, and a small amount bleeding on the cutting surface. A neighboring small mass of 6.5 mm in diameter existed (arrow). B. Histological examination revealed that the tumor showed that there were many epithelioid myoid cells, epithelioid clear cells with sinusoidal vessels, and mature adipose tissues (H & E staining, objective; ×40). C. Immunohistochemical analysis revealed that epithelioid myoid cells showed high expression of HMB-45 (objective; ×40). D. Many capillaries positive for CD34 antigen had grown (objective; ×20). E. The Ki67 index was 0.3% (objective; ×40). F. The tumor cells were negative for c-kit (CD117), and only plasma cells were positive (objective; ×20). G. Expression of TSC1/hamartin reduced in comparison with surrounding liver tissue (tumor; left lower, normal liver; right upper, objective; ×20). H. Elastica-Masson stain. Tumor infiltrated into hepatic veins (objective; ×4).