Myxoid liposarcoma with gastric localisation – Case Report

Abstract Liposarcoma is the most common malignant mesenchymal neoplasm affecting soft tissues and, less frequently, viscera. Gastric localisation of liposarcoma is extremely rare. We present the case of a 69-year-old female patient, who underwent subtotal gastrectomy with processing of the specimen in the Clinical Service of Pathology, Emergency County Hospital of Constantza. Histopathologically, the tumor exhibits a neoplastic population composed predominantly of lipoblasts in different stages of differentiation, with a massive disposition involving submucosa, muscularis and serosa. These cells contain intracytoplasmic small optically empty lipid vacuoles that produce indentations of centrally located nuclei; isolated lipoblasts have the appearance of signet ring cells. Predominant cellular population is admixed with scattered mature adipocytes and with stellate/spindled mesenchymal cells. Tumoral stroma has a myxoid character. A distinctive feature of this neoplasm is the existence of a vascular network composed of curved thin-walled capillaries with a branching pattern (“chicken-wire”). The histopathological traits and immunohistochemical profile of this tumor, characterized by positive reaction to Vimentin and S100 and negative staining to pancytokeratin, support the diagnosis of myxoid liposarcoma. The rare incidence of this tumor in the stomach requires a careful microscopical examination, in order to differentiate it from other clinico-pathological entities and to apply an appropriate therapy with a proper monitoring protocol.