淋巴瘤是感染 FeLV 的猫中最常诊断出的肿瘤之一。结外淋巴瘤包括眼部和眼周组织的淋巴瘤，例如第三眼睑（T​​EL），这是猫中一种不常见的诊断类型淋巴瘤。本研究旨在描述两只感染 FeLV 的猫 TEL 淋巴瘤的临床病理特征。在两个解剖病理学实验室进行回顾性研究，有两例符合纳入标准。一只 4 岁母猫（病例 1），免疫组织化学（IHC）检测 FIV gp40 抗原和 FeLV gp70 抗原呈阳性，以及一只 22 个月大的雄性猫（病例 2），FeLV p27 抗原和 FeLV p27 抗原血清学阳性病例 2 经 IHC 检测 FeLV gp70 抗原，因 TEL 单侧肿胀和肿块被转诊至兽医诊所，病例 2 肿块快速生长。组织学和免疫组织化学分析最终诊断为两例弥漫性大 B 细胞淋巴瘤。病例 2 的猫在诊断后 4 个月内死亡，死亡前临床症状恶化。两种情况均未进行尸检，这排除了原发性或继发性受累的定义。然而，眼部病变是两例就诊的原因，并且可能是多中心疾病的最初表现。因此，临床发现眼睑肿胀或肿块形成的 FeLV 感染猫应将淋巴瘤作为鉴别诊断，并应进行全面的体检以检测眼外受累情况。© 2024 美国兽医眼科医师学会。

Lymphoma is one of the most frequently diagnosed tumors in FeLV-infected cats. Extranodal lymphomas include lymphomas in ocular and periocular tissues, such as the third eyelid (TEL), which is an uncommonly diagnosed type of lymphoma in cats. This study aimed to describe the clinicopathological features of lymphoma in the TEL of two FeLV-infected cats. A retrospective study in two anatomic pathology laboratories was performed, and two cases met the inclusion criteria. A 4-year-old, female cat (case 1), positive for FIV gp40 antigen and FeLV gp70 antigen by immunohistochemistry (IHC), and a male cat of 22 months old (case 2), positive both serologically for FeLV p27 antigen and for FeLV gp70 antigen by IHC, were referred to veterinary clinics with unilateral swelling and mass in the TEL, which had rapid growth in case 2. Histological and immunohistochemical analysis established the final diagnosis of diffuse large B-cell lymphoma in both cases. The cat in case 2 died 4 months after the diagnosis, with clinical worsening prior to death. Necropsy was not performed in either case, which precluded the definition of a primary or secondary involvement. However, the ocular lesions were the reason for consultation in both cases and it may have been an initial manifestation of a multicentric disease. Thus, FeLV-infected cats with clinical finding of eyelid swelling or mass formation should have lymphoma as a differential diagnosis, and a complete physical examination should be performed to detect extraocular involvement.© 2024 American College of Veterinary Ophthalmologists.