最近，已经发现了发生在主要唾液腺中的胸腺样分化（CASTLE）癌病例。为了评估 CD5 免疫组织化学在区分唾液腺 CASTLE 与其他类型唾液腺肿瘤中的诊断价值，我们评估了 109 个唾液腺肿瘤中的 CD5 表达，涵盖 23 种不同的组织学类型，包括唾液腺 CASTLE。此外，我们回顾了之前报道的 10 例唾液 CASTLE 病例。大多数唾液CASTLE病例（10/11，91%）显示出强烈的CD5表达。相比之下，108 个非唾液腺 CASTLE 肿瘤中的 104 个 (96%) CD5 呈阴性，而其余 4 个肿瘤 (3.7%)（所有这些肿瘤在组织学上均为 Warthin 肿瘤）显示 CD5 局灶性阳性，强度为弱至中度。总之，本研究的结果支持 CD5 免疫组织化学可用于区分唾液腺 CASTLE 与其他组织学类型的唾液腺肿瘤。该肿瘤中异常的 CD5 表达可能与肿瘤微环境有关。© 2023。作者获得 Springer-Verlag GmbH 德国（Springer Nature 旗下公司）的独家许可。

Recently, cases of carcinoma showing thymus-like differentiation (CASTLE) occurring in major salivary glands have been identified. To assess the diagnostic value of CD5 immunohistochemistry in distinguishing salivary CASTLE from other types of salivary gland tumors, we evaluated CD5 expression in 109 salivary gland tumors, encompassing 23 different histological types, including salivary CASTLE. In addition, we reviewed 10 previously reported cases of salivary CASTLE. Most salivary CASTLE cases (10/11, 91%) showed strong CD5 expression. In contrast, 104 of 108 (96%) non-salivary CASTLE tumors were negative for CD5, while the remaining four tumors (3.7%), all of which were histologically Warthin tumors, showed focal positivity for CD5 with weak to moderate intensity. In conclusion, the findings in this study support the potential use of CD5 immunohistochemistry for distinguishing salivary CASTLE from other histological types of salivary gland tumors. Aberrant CD5 expression in this tumor may be linked to the tumor microenvironment.© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.