Fig. 2 From: Successful treatment based on molecular biological assessment of invasive anaplastic lymphoma kinase-positive inflammatory myofibroblastic tumor of the lunga Histopathological examination demonstrated proliferation of spindle cells and collagen fiber, and the infiltration of plasma cells and lymphocytes (× 100). b ALK expression was positive in the spindle cells (× 400). c There were a lot of IgG-positive plasma cells (× 100). d On the other hand, few cells were positive for IgG4-positive plasma cells (× 100)Back to article page