A lactating 20-year-old, brown, Arabian mare, weighing about 300 kg, presented for bleeding from one teat and severe swelling of the entire mammary gland. The mare had untreated mastitis 10 months before. Consequently, a gangrenous teat developed after chronic bloody and purulent discharges. The teat was removed surgically by the field veterinarian. At that time, the mammary gland increased in size. Bloody and purulent discharges restarted 10 days previously. Under general anaesthesia, the entire mammary gland was removed. Comedocarcinoma was diagnosed by histopathological assessment. Immunohistochemical staining was performed for pan-cytokeratin and vimentin. Microscopic examination of immunohistochemical stained slides revealed expression of pan-cytokeratin. In conclusion, this report describes clinical, macroscopic, histopathological and immunohistochemical characteristics of comedocarcinoma that did not metastasise to regional lymph nodes. Reports in the field of equine oncology contribute to improved general knowledge in equine medicine, contributing to better diagnosis and treatment.

中文翻译：

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阿拉伯母马乳腺粉刺癌的手术治疗：术后管理、组织病理学和免疫组织化学特征

一匹哺乳期的 20 岁棕色阿拉伯母马，重约 300 公斤，因一个乳头出血和整个乳腺严重肿胀就诊。这匹母马在 10 个月前患有未经治疗的乳腺炎。因此，在慢性血性和脓性分泌物后形成坏疽的乳头。现场兽医通过手术切除了乳头。那时，乳腺变大了。10 天前又出现血性和脓性分泌物。在全身麻醉下，切除了整个乳腺。通过组织病理学评估诊断粉刺癌。对泛细胞角蛋白和波形蛋白进行免疫组织化学染色。免疫组织化学染色载玻片的显微镜检查显示泛细胞角蛋白的表达。总之，本报告描述了临床、宏观、未转移至区域淋巴结的粉刺癌的组织病理学和免疫组织化学特征。马肿瘤学领域的报告有助于提高马医学的一般知识，有助于更好的诊断和治疗。