Lovell Ser, Burchell R K, Roady P J, Fredrickson R L, Gal A
Animal Referral Centre, Auckland, New Zealand.
Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Private Bag 11-222, Palmerston North, 4442, New Zealand.
BMC Vet Res. 2017 Aug 16;13(1):247. doi: 10.1186/s12917-017-1181-6.
Canine joint sarcomas, designated synovial sarcomas, are uncommon malignant mesenchymal neoplasms that occur in the large joints of the extremities of middle-aged, large-breed dogs. We report the diagnosis of an intrathoracic sarcoma with ultrastructural characteristics reminiscent of human synovial sarcoma in a dog.
A 7-year-old female spayed Tibetan terrier crossbred dog was presented for acute severe labored breathing and diagnosed with an intrathoracic neoplastic mass. The neoplasm resulted in the accumulation of substantial amounts of viscous pleural fluid that led to dyspnea. The neoplastic mass consisted of interweaving bundles of large pleomorphic mesenchymal cells, supported by an alcian blue positive myxomatous matrix. The neoplastic cells were immunohistochemically negative for cytokeratin and CD18. Transmission electron microscopy indicated that the neoplastic cells had desmosome junctions, short microvilli-like structures and ample amounts of rough endoplasmic reticulum resembling type B-like synoviocytes and synovial sarcoma as reported in people. Despite complete surgical excision of the neoplastic mass, clinical signs recurred after a month and led to the euthanasia of the dog.
Currently, there are no immunohistochemical markers specific for synovial sarcoma. Canine neoplasms with transmission electron microscopy characteristics resembling type B-like synoviocytes should be considered similar to the human sarcomas that carry the specific translocations between chromosomes X and 18.
犬关节肉瘤，即滑膜肉瘤，是一种罕见的恶性间充质肿瘤，发生于中年大型犬种四肢的大关节处。我们报告了一例犬胸腔内肉瘤的诊断，其超微结构特征使人联想到人类滑膜肉瘤。
一只7岁已绝育的藏獒杂交母犬因急性严重呼吸困难前来就诊，被诊断为胸腔内肿瘤性肿块。该肿瘤导致大量粘性胸腔积液积聚，引起呼吸困难。肿瘤性肿块由交织成束的大的多形性间充质细胞组成，由阿尔辛蓝阳性的黏液样基质支持。肿瘤细胞免疫组化检测细胞角蛋白和CD18均为阴性。透射电子显微镜检查表明，肿瘤细胞具有桥粒连接、短的微绒毛样结构和大量粗面内质网，类似于人类报道的B型滑膜细胞和滑膜肉瘤。尽管手术完整切除了肿瘤性肿块，但一个月后临床症状复发，导致该犬实施安乐死。
目前，尚无滑膜肉瘤特异性的免疫组化标志物。具有类似于B型滑膜细胞超微结构特征的犬肿瘤应被视为与人类携带X染色体和18号染色体之间特定易位的肉瘤相似。
