Inflammatory myofibroblastic tumor of the distal common bile duct: Literature review with focus on pathological examination

Figure 1 Inflammatory myofibroblastic tumor of the common bile duct. A: Macroscopic picture showing a gelatinous lesion in the lumen of the intrapancreatic part of the common bile duct; B: Microscopic examination of the same lesion confirming its myxoid nature (hematoxylin and eosin, original magnification 10x).

Figure 2 Histological and immunohistochemical characteristics. A: At high magnification this inflammatory myofibroblastic tumor is composed of plump spindle cells with a vesicular nucleus and pale cytoplasm. The stroma is myxoid with an inflammatory infiltrate composed of lymphocytes, plasma cells, macrophages and scarce eosinophils (hematoxylin and eosin, original magnification, 100x); B: The lesion demonstrates obvious ALK positivity in the spindle cells (original magnification 500x).