2例犬口腔肉瘤的病理学分析

Pathological Analysis of Two Cases of Canine Oral Sarcoma

口腔肉瘤是犬常见的口腔肿瘤,尤其在老年犬多发。本试验通过苏木精-伊红(H.E.)染色和免疫组织化学检测对2例犬口腔肿物进行组织病理学分析。H.E.染色结果显示,2例患犬肿物组织可见大量增生的梭形细胞和局部黑色素颗粒,伴随继发性出血和坏死性囊变,高倍镜下细胞具多形性和异型性,核仁明显,核分裂象易见,初步诊断为恶性黑色素瘤或软组织肉瘤。免疫组织化学检测结果显示,2例患犬口腔肿物中广谱细胞角蛋白(CKp)表达均呈阴性,波形蛋白(Vimentin)表达均呈阳性,1号犬上皮细胞膜抗原(EMA)和2号犬人角蛋白抗原决定簇(Cam5.2)表达均呈阴性,可知肿瘤是间质来源;黑色素-A(Melan-A)、钙结合蛋白(S-100)和人类黑色素瘤标志物-45(HMB45)等特异性抗体表达均呈阴性,故黑色素瘤和神经鞘肉瘤的可能性不高。1号犬中α-平滑肌肌动蛋白(SMA)、中间丝状体蛋白(Desmin)在部分区域呈阳性,肌细胞生成素(Myogenin)呈阴性,考虑部分肌源性分化;2号犬无肌源性标志物表达。综合分析,2例患犬口腔肿物均为高级软组织肉瘤。

Oral sarcomas are common oral tumors in dogs,particularly in geriatric dogs.In this study,two cases of oral masses in dogs were subjected to histopathological analysis using hematoxylin and eosin(H.E.)staining and immunohistochemistry detection.H.E.staining revealed proliferating spindle cells and local melanin granules in the tumor tissues of both dogs.Secondary hemorrhage and necrotic cystic changes were observed.Under high magnification,cells exhibited pleomorphism,atypia,prominent nucleoli,and frequent mitosis,leading to a preliminary diagnosis of malignant melanoma or soft tissue sarcoma.Immunohistochemical results showed negative expression of broad-spectrum cytokeratin(CKp)and positive expression of vimentin in both cases,epithelial membrane antigen(EMA)in case 1 and human cytokeratin antigen cluster(Cam5.2)in case 2 were negatively expressed,indicating an interstitial origin of the tumor.Specific antibodies such as Melan-A,S-100,and human melanoma black-45(HMB45)were all negative,reducing the possibility of melanoma and nerve sheath sarcoma.In case 1,α-smooth muscle actin(SMA)and Desmin were partially positive in some areas,suggesting partial myogenic differentiation.Case 2 showed no expression of myogenic markers.In conclusion,both cases of oral masses in dogs were diagnosed as high-grade soft tissue sarcomas.