Lymphomatoid granulomatosis (LYG) is a rare variant of an angioinvasive T-cell lymphoproliferative disorder that primarily affects the lungs, with common sites of metastasis including the skin and subcutis. In humans, it is a B-cell lymphoproliferative disorder associated with Epstein-Barr virus infection. Our case is a 7-y-old, spayed female, domestic longhair cat that decompensated and was euthanized following an initial diagnosis of angioinvasive lymphoma from a skin biopsy. Autopsy revealed nodules in the lungs and subcutis, and corneal thickening and cloudiness. Histologic examination of cutaneous nodules, lungs, and eye showed similar angioinvasive cellular infiltrates and pattern to that of the original skin biopsy, consistent with a diagnosis of LYG. The neoplastic cells displayed CD3-positive immunoreactivity in the skin, eye, and lung, and PCR for antigen receptor rearrangement (PARR) showed T-cell clonality in all tissues tested. This is the third case of LYG to be reported in cats and is the only case in which PARR analysis and immunophenotyping immunohistochemical staining was performed. LYG with ocular involvement has not been reported previously in cats, to our knowledge. Our case demonstrates the necessity for considering LYG when presented with a cat with respiratory signs in conjunction with subcutaneous nodules and ocular lesions.

淋巴瘤样肉芽肿病 (LYG) 是一种罕见的血管侵袭性 T 细胞淋巴增生性疾病，主要影响肺部，常见的转移部位包括皮肤和皮下组织。在人类中，它是一种与 Epstein-Barr 病毒感染相关的 B 细胞淋巴增生性疾病。我们的病例是一只 7 岁的已绝育雌性家养长毛猫，在皮肤活检初步诊断为血管侵袭性淋巴瘤后失代偿并被安乐死。尸检发现肺部和皮下组织有结节，角膜增厚和混浊。皮肤结节、肺和眼的组织学检查显示与原始皮肤活检相似的血管侵袭性细胞浸润和模式，与 LYG 的诊断一致。肿瘤细胞在皮肤、眼睛和肺中表现出 CD3 阳性免疫反应性，抗原受体重排 (PARR) 的 PCR 显示所有测试组织中的 T 细胞克隆性。这是猫中报告的第三例 LYG，也是唯一进行了 PARR 分析和免疫表型免疫组织化学染色的病例。据我们所知，之前在猫中没有报道过眼部受累的 LYG。我们的案例表明，当一只猫出现呼吸症状并伴有皮下结节和眼部病变时，考虑 LYG 的必要性。