NOTE Pathology Lymphangiosarcoma with systemic metastases in a Japanese domestic cat

ABSTRACT. A 4-year-2-month-old female Japanese domestic cat was diagnosed with lymphangiosarcoma through tissue biopsy of an am-putated leg. Two months later, the cat was euthanized, and postmortem findings revealed edema, and bruising at the caudal region of the trunk, pulmonary hemorrhage, pulmonary nodules and mediastinal lymphadenopathy. Microscopically, neoplastic tissues were observed in the dermis and subcutis of the trunk, lung, mediastinal lymph nodes, diaphragm, omentum and mesentery. The tumor cells were spindle to polygonal-shaped with nuclear pleomorphism aligning along pre-existing collagen bundles and forming irregular vascular channels in which the erythrocytes were rarely observed. These cells were immunopositive for vimentin, von Willebrand factor and CD31. Based on the histopathological and immunohistochemical features, the neoplasia was diagnosed as lymphangiosarcoma with systemic metastases. KEY WORDS: feline, lymphangiosarcoma, metastases doi: 10.1292/jvms.14-0502; J. Vet. Med. Sci. 77(3): 371–374, 2015 Lymphangiosarcoma is an extremely rare malignant tumor in humans and domestic animals. This tumor arises from the lymphatic endothelial cells of the lymph vessel and occurs in any part of the body [4, 5, 7, 12, 16, 20]. In humans, most cases of lymphangiosarcoma are associated with secondary chronic lymphedema, particularly in women who have bee