Figure 5

Pathological findings. (a) microscopic examination of the paraffin section of the liver ‘tumor’ showed that it was composed of fascicles of spindle cells such as fibroblasts and myofibroblasts accompanied by many lymphocytes, plasma cell, neutrophils, and macrophages. No mitotic cells were observed in these spindle cells (H&E stain, ×200). Immunohistochemical (IHC) studies of spindle cells showed positive staining for smooth muscle actin (SMA) (b) and negative staining for desmin (c) and CD34 (d). IHC studies of white blood cells revealed that the majority of lymphocytes expressed CD3 (e) and some cells expressed CD20 (f). Moreover, IHC showed some IgG4-positive plasma cells (g).