一例犬胫骨非骨化性纤维瘤的诊断

Diagnosis report of a case of canine tibial non-ossifying fibroma

1只2岁哈士奇,右后肢悬空,行走困难,疼痛反应明显,饮食、驱虫及免疫均正常,没有发生碰撞。对患犬进行血常规、血清生化指标检查,以及数字X线摄影(digital radiography,DR)和电子计算机断层扫描(computed tomography,CT)检查,并在手术后进行病理剖检、苏木精-伊红染色(hematoxylin-eosin staining,H.E.)染色和免疫组织化学检查。结果表明:血清总蛋白、球蛋白含量和淀粉酶活性降低,血磷含量升高;DR影像显示患犬右后肢胫骨近端出现近似长楔形的低密度阴影区,病灶紧靠骨皮质,且长轴与骨干平行。CT影像显示患犬右后肢胫骨近端骨密度降低,部分骨组织已发生破坏、溶解,骨皮质变薄。病理剖检显示病变骨组织的颜色为黄白色,质地较脆,病变的边界呈一条清晰可见的红色带状;H.E.染色镜检可见大量梭形细胞增生,细胞排列杂乱无序;免疫组织化学检查结果显示有少量肿瘤细胞核呈棕黄色,骨肿瘤标志物波形纤维蛋白呈弱阳性,肿瘤细胞大多分布在有纤维细胞聚集的纤维束附近,诊断为犬胫骨非骨化性纤维瘤。说明犬胫骨骨肿瘤具有特征性的DR和CT影像学表现,影像学诊断可准确确定其病变位置及大小,但是骨肿瘤的性质还是需要病理剖检进行确诊,有助于临床宠物诊疗方案的制订。

A 2-year-old Husky had a dangling right hind limb, difficulty in walking, obvious pain response, normal diet, deworming and immunity, and no collision occurred. Routine blood, serum biochemical indexes, digital radiography(DR) and computed tomography(CT) examinations were performed on the dog. Pathological autopsy, hematoxylin-eosin staining(H.E.) staining and immunohistochemical examinations were performed after surgery. The results showed that the contents of total protein, globulin and amylase activity in serum decreased, and the content of blood phosphorus increased;DR imaging showed that an approximately long wedge low-density shadow area appeared in the proximal tibia of the right hind limb. The lesion was close to the cortical bone, and the long axis was parallel to the diaphysis. CT imaging showed that the bone density of the proximal tibia of the right hind limb of the dog was decreased, and some bone tissues had been broken and dissolved, and the bone cortex had become thinner. Pathological autopsy showed that the color of the diseased bone tissue was yellow-white;the texture was relatively fragile, and the boundary of the disease presented a clearly visible red band. Microscopic examination of H.E. staining showed that a large number of spindle cells proliferated, and the cells were arranged in disorder. Immunohistochemical examination results showed that a small number of tumor cell nuclei were brownish-yellow, and the bone tumor marker Vimentin was weakly positive;most of the tumor cells were distributed near the fibrous bundles with fibrocytic aggregation, and the diagnosis was canine tibia non-ossifying fibroma. The results suggested that canine tibial bone tumors had characteristic DR and CT imaging manifestations, and imaging diagnosis could accurately determine the location and size of the lesions, but the nature of bone tumors still required pathological autopsy to confirm the diagnosis, which was helpful for the formulation of clinical pet diagnosis and treatment programs.