成人 T 细胞白血病/淋巴瘤 (ATLL) 是一种侵袭性外周 T 细胞肿瘤，预后不良。具有免疫球蛋白和免疫受体酪氨酸抑制基序结构域 (TIGIT) 的 T 细胞免疫受体是 T 细胞和自然杀伤细胞上表达的免疫检查点受体。尽管肿瘤微环境中 TIGIT 表达增加与各种肿瘤的不良预后相关，但其在 ATLL 中的相关性仍不清楚。在此，我们使用免疫组织化学研究了 TIGIT 表达对 ATLL 的临床病理学影响。 84 名患者中有 21 名 (25%) 检测到 TIGIT 表达。发现临床特征与免疫检查点分子和 TIGIT 表达之间存在部分关联，包括 sIL-2R、CD86 和 GITR。与 TIGIT 阴性患者（MST 18.7 个月，95% CI 12.0-36.4）相比，TIGIT 阳性患者 [中位生存时间 (MST) 8.9 个月，95% 置信区间 (CI) 7.7-15.6] 的总生存期较差 (p= TIGIT 表达在单变量和多变量分析中均保持其预后价值 [风险比 (HR) 1.909；95% CI 1.044-3.488；p=0.0356]。 ATLL 患者中的 TIGIT 表达。版权所有 © 2024 澳大利亚皇家病理学家学院，由 Elsevier B.V 出版。保留所有权利。

Adult T-cell leukaemia/lymphoma (ATLL) is an aggressive peripheral T-cell neoplasm with a poor prognosis. T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domains (TIGIT) is an immune checkpoint receptor expressed on T and natural killer cells. Although increased TIGIT expression in the tumour microenvironment is associated with poor prognosis in various neoplasms, its relevance in ATLL remains unknown. Herein, we investigated the clinicopathological impact of TIGIT expression on ATLL using immunohistochemistry. TIGIT expression was detected in 21 of 84 patients (25%). A partial association between the clinical features and immune checkpoint molecules and the expression of TIGIT was found including sIL-2R, CD86 and GITR. TIGIT-positive patients [median survival time (MST) 8.9 months, 95% confidence interval (CI) 7.7-15.6] had inferior overall survival compared with TIGIT-negative patients (MST 18.7 months, 95% CI 12.0-36.4) (p=0.0124]. TIGIT expression maintained its prognostic value for overall survival in both univariate and multivariate analyses [hazard ratio (HR) 1.909; 95% CI 1.044-3.488; p=0.0356]. Further studies are required to clarify the clinical and biological significance of TIGIT expression in patients with ATLL.Copyright © 2024 Royal College of Pathologists of Australasia. Published by Elsevier B.V. All rights reserved.