Inflammatory myofibroblastic tumor of the pancreas in a dog

Abstract

A large, ill-defined, firm, multinodular mass involving the pancreas was confirmed on postmortem examination of a 5-y-old, male Rottweiler that died following acute respiratory distress syndrome, after a period of anorexia and lethargy. Histologically, the mass consisted of plump spindle cells admixed with a variable number of macrophages, lymphocytes, plasma cells, and neutrophils. Foci of coagulative necrosis and hemorrhage were also observed. Spindle cells strongly reacted to antibodies against vimentin, α–smooth muscle actin, and calponin, whereas desmin was expressed only mildly and focally. Pan-cytokeratin, KIT, glial fibrillary acidic protein, and S100 protein were nonreactive. Variable numbers of MAC 387–positive cells, CD3+ lymphocytes, and numerous blood vessels were also detected throughout the mass. Histologic and IHC findings were consistent with a diagnosis of inflammatory myofibroblastic tumor of the pancreas.

Clinicopathologic features and biologic behavior of canine splenic nodules with stromal, histiocytic and lymphoid components

“…Virusinduced trauma, surgery, autoimmune etiology, inflammation, infection, and abnormal responses to long-standing exogenous stimuli may result in tumorigenesis (9, 10). IMT has been rarely reported in dogs in various anatomic location, including skin, pancreas, urinary bladder and retrobulbar region, although the immunohistochemical expression of muscular markers was different from that reported in the current study (11)(12)(13).…”

Multifocal spinal inflammatory myofibroblastic tumors in a juvenile paraparetic dog

“…Spinal location is rare, and the imaging features are variable with overlapping features with other spinal tumors such as meningioma due to the presence of a dural tail, lymphoma, or metastatic neoplasia, however bone involvement is not a reported feature of spinal IMT 9 . In veterinary medicine IMTs have been described in various species and multiple anatomic locations such as the urinary bladder, 1 spleen, 4,10 pancreas, 5 mitral valve, 11 nasal cavity, 12 retrobulbar space, 13 peritoneum, 14 and rarely within the spinal canal of dogs. Intramedullary, intradural extramedullary, and extradural localized solitary IMT's have been described in dogs, 2,3,15 however, multifocal spinal presentation as shown herein has not been previously reported.…”

“…Inflammatory myofibroblastic tumors are characterized as myofibroblastic cells admixed with various inflammatory cells including lymphocytes, plasma cells, neutrophils, and histiocytes 1–5 . There is continued debate in the veterinary literature as to whether these represent true neoplasia, or inflammation, or a mixture of both.…”

“…Inflammatory myofibroblastic tumors are characterized as myofibroblastic cells admixed with various inflammatory cells including lymphocytes, plasma cells, neutrophils, and histiocytes. [1][2][3][4][5] There is continued debate in the veterinary literature as to whether these represent true neoplasia, or inflammation, or a mixture of both. The pathogenesis is not fully understood, and this is reflected in the use of variable nomenclature such as IMT, inflammatory pseudotumor, inflammatory fibrosarcoma, plasma cell granuloma.…”

Superficial angiomyxoma in a pregnant cow

“…Multiple samples of the mass were fixed in 10% neutral buffered formalin, wax-embedded for histology, and 5- μ m thick sections were stained with haematoxylin and eosin. Additional sections of the mass were also stained with alcian blue at pH 2.5 and subjected to immunohistochemistry using primary antibodies directed against vimentin (1 in 100 dilution, V9, mouse monoclonal; DAKO), α-smooth muscle actin (α-SMA; 1 in 400 dilution, 1A4, mouse monoclonal; DAKO), desmin (1 in 50 dilution, D33, mouse monoclonal; DAKO), and von Willebrand factor (vWF; 1 in 400 dilution, rabbit polyclonal; DAKO), according to a previously-described technique (Romanucci et al 2019 ). Immune complexes were treated with secondary biotinylated goat anti-mouse or anti-rabbit antibody (1 in 200 dilution; Vector Laboratories, Inc., Burlingame, CA) and subsequently detected using an avidin-biotin complex (ABC) method (Vectastain® ABC Kit; Vector Laboratories, Inc.).…”