Dobromylskyj Melanie J, Copas Victoria, Durham Andy, Hughes Thomas K, Patterson-Kane Janet C
School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, Scotland.
J Vet Diagn Invest. 2011 May;23(3):615-8. doi: 10.1177/1040638711403902.
A 9-year-old Haflinger mare presented to the Liphook Equine Hospital with a history of weight loss, azotemia, and repeated episodes of ascites over a period of 10 days. The horse was euthanized after exploratory laparotomy revealed large numbers of variably sized masses distributed throughout the peritoneal cavity. Macroscopically, some masses were papillary, while others were nodular. Histologically, the masses were comprised of large to giant, variably shaped, and occasionally multinucleated neoplastic cells with marked anisokaryosis and anisocytosis and a high mitotic rate. Small to moderate numbers of neoplastic cells were swollen by 1 to several, moderately sized to large, clear, circular or ovoid vacuoles, which stained positive with oil red O. Immunohistochemically, the neoplastic cells co-expressed vimentin and cytokeratin. Electron microscopy demonstrated tumor cells with tight junctions, microvilli, and numerous intracytoplasmic lipid droplets. These findings are consistent with a lipid-rich form of mesothelioma, which should be considered as a differential diagnosis if lipid vacuoles are present in potentially neoplastic cells in equine abdominocentesis samples.
一匹9岁的哈福林格母马被送至利普胡克马医院，病史显示其在10天内出现体重减轻、氮血症和反复腹水发作。在剖腹探查发现大量大小不一的肿块分布于整个腹腔后，该马被实施安乐死。宏观上，一些肿块呈乳头状，而其他的则为结节状。组织学上，这些肿块由大到巨大、形状各异、偶尔多核的肿瘤细胞组成，具有明显的核大小不一和细胞大小不一，且有高有丝分裂率。少量至中等数量的肿瘤细胞被1至几个中等大小至大的、透明的、圆形或椭圆形空泡所充盈，油红O染色呈阳性。免疫组化显示，肿瘤细胞同时表达波形蛋白和细胞角蛋白。电子显微镜显示肿瘤细胞有紧密连接、微绒毛和大量胞质内脂质小滴。这些发现与富含脂质的间皮瘤相符，如果在马腹腔穿刺样本中潜在的肿瘤细胞中存在脂质空泡，则应将其视为鉴别诊断之一。
