Leiomiosarcoma con patrón fusocelular y epitelioide en cuerpo del páncreas. Utilidad de la inmunohistoquímica en el diagnóstico diferencial de las neoplasias mesenquimales pancreáticas

Pancreatic leiomyosarcoma is a highly aggressive malignancy with a poor prognosis. We report a case of a 78-year-old man with an abdominal mass which was diagnosed radiologically as a primary pancreatic sarcoma. Histopathology revealed a spindle/epithelioid cells morphology and immunohistochemistry showed strong positivity for smooth muscle actin and desmin, with negative results for myogenin, h-caldesmon, CD117, DOG-1, S100, MyoD1, chromogranin-A, HMB-45, Melan-A and EBV. The diagnosis of spindle and epithelioid leiomyosarcoma was confirmed. The differential diagnosis with pancreatic mesenchymal lesions is discussed.