Siripoonsub Jedsada, Sirivisoot Sirintra, Techangamsuwan Somporn, Rungsipipat Anudep
Center of Excellence for Companion Animal Cancer, Department of Pathology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330 Thailand.
Vet World. 2024 Oct;17(10):2225-2234. doi: 10.14202/vetworld.2024.2225-2234. Epub 2024 Oct 4.
Feline lymphomas are categorized based on the location of tumor cells, with anatomical classifications including alimentary, mediastinal, multicentric, and extranodal forms. Accurate diagnosis and classification of feline lymphoma are paramount for enhancing treatment and prognosis. T-cell lymphomas are CD3 positive, while B-cell lymphomas exhibit positive forCD20, CD79α, and paired box 5 (PAX5). The aims of this study were (1) to classify feline lymphoma in each anatomical subtype using the World Health Organization (WHO) classification to provide information on epidemiological findings; (2) to investigate the expression and detection of B-cell lymphoma, various antibodies will be used, with the addition of PAX5, for clearer results; and (3) to gather more extensive information about feline lymphoma in Thailand, particularly in the Bangkok area.
From 2011 to 2023, 86 sample tissues were submitted for routine pathological examination at the Department of Pathology, Faculty of Veterinary Science, Chulalongkorn University. Immunohistochemistry (IHC) was performed to detect an immunophenotype of PAX5, CD79α, CD20 (B-cell lineage), and CD3 (T-cell lineage). Eighty-six formalin-fixed, paraffin-embedded lymphoma tissues were prepared on silane-coated slides. After IHC, all cases were classified according to the WHO classification.
The most common form of lymphoma in this study was extranodal lymphoma at 37.2% (32/86), followed by multicentric lymphoma at 31.3% (27/74), mediastinal lymphoma at 17.4% (15/86), and alimentary lymphoma at 14% (12/86). Most extranodal lymphoma cases were in the nasal region. From the anatomical form, multicentric and extranodal lymphomas were predominantly diffuse large B-cell high-grade, while mediastinal lymphomas were small low-grade B-cell lymphomas. Alimentary lymphomas occur in various types, with most being the B-cell type.
This study indicates that extranodal lymphoma and extranodal lymphoma are the most frequent presentations found in cats in Bangkok. Mediastinal and alimentary lymphomas still occur. The utilization of various B-cell markers in combination could aid pathologists in distinguishing between various stages of B-cell maturation, assessing tumor cell heterogeneity, and determining the phenotype in scenarios where there is a loss of common B-cell markers diffuse large B-cell lymphomas is the most prevalent subtype of feline lymphoma. Significantly, relying solely on immunochemistry with one parameter may not be sufficient for a definitive diagnosis of B-cell lymphoma, as another parameter may also be necessary.
猫淋巴瘤根据肿瘤细胞的位置进行分类，解剖学分类包括消化道型、纵隔型、多中心型和结外型。猫淋巴瘤的准确诊断和分类对于改善治疗及预后至关重要。T细胞淋巴瘤CD3呈阳性，而B细胞淋巴瘤CD20、CD79α和配对盒5（PAX5）呈阳性。本研究的目的是：（1）使用世界卫生组织（WHO）分类对每种解剖学亚型的猫淋巴瘤进行分类，以提供流行病学调查结果信息；（2）研究B细胞淋巴瘤的表达和检测，将使用多种抗体，并增加PAX5以获得更清晰的结果；（3）收集泰国尤其是曼谷地区关于猫淋巴瘤更广泛的信息。
2011年至2023年，86份样本组织提交给朱拉隆功大学兽医学院病理学系进行常规病理检查。采用免疫组织化学（IHC）检测PAX5、CD79α、CD20（B细胞谱系）和CD3（T细胞谱系）的免疫表型。在硅烷包被的载玻片上制备86份福尔马林固定、石蜡包埋的淋巴瘤组织。免疫组织化学检测后，所有病例根据WHO分类进行分类。
本研究中最常见的淋巴瘤类型是结外型淋巴瘤，占37.2%（32/86），其次是多中心型淋巴瘤，占31.3%（27/74），纵隔型淋巴瘤占17.4%（15/86），消化道型淋巴瘤占14%（12/86）。大多数结外型淋巴瘤病例位于鼻腔区域。从解剖学形式来看，多中心型和结外型淋巴瘤主要是弥漫性大B细胞高级别淋巴瘤，而纵隔型淋巴瘤是小B细胞低级别淋巴瘤。消化道型淋巴瘤有多种类型，大多数为B细胞型。
本研究表明，结外型淋巴瘤是曼谷地区猫中最常见的类型。纵隔型和消化道型淋巴瘤仍有发生。联合使用多种B细胞标志物有助于病理学家区分B细胞成熟的不同阶段、评估肿瘤细胞异质性以及在常见B细胞标志物缺失的情况下确定表型。弥漫性大B细胞淋巴瘤是猫淋巴瘤中最常见的亚型。重要的是，仅依靠单一参数的免疫化学可能不足以确诊B细胞淋巴瘤，可能还需要另一个参数。
