原发性肠道 T 细胞和自然杀伤细胞淋巴瘤 (PITNKL) 具有侵袭性，使得活检标本的病理诊断具有挑战性。我们分析了不同亚型的临床病理特征和治疗结果。79例PITNKL病例具有临床、形态学和免疫组化特征。在我们机构2008年至2017年的79例PITNKL中，40例（50.63%）为结外NK/T -鼻型细胞淋巴瘤（ENKTL）； 32 (40.51%) 单形性上皮性肠道 T 细胞淋巴瘤 (MEITL)； 6（7.59%）肠T细胞淋巴瘤，未另有说明； 1 例（1.27%）胃肠道惰性 T 细胞淋巴瘤。小肠 (n = 47) 是最常见的部位。单形性上皮性肠道 T 细胞淋巴瘤与其他亚型具有明显的临床病理特征，其中脾酪氨酸激酶 (SYK) 和 PD-L1 (87.5%) 高表达 (96.88%)，且预后最差 (P < .001)。 CD30在ENKTL中高表达(9/17, 57.94%)，与预后无关(P > .05)。PITNKL病例具有生物学异质性；大多数预后不佳。 SYK 和 PD-L1 表达可能是 MEITL 的重要标志物，有助于鉴别诊断。© 美国临床病理学会，2024 年。

Primary intestinal T-cell and natural killer-cell lymphomas (PITNKLs) are aggressive and make pathologic diagnoses in biopsy specimens challenging. We analyzed different subtypes' clinicopathologic features and treatment outcomes.Seventy-nine PITNKL cases were characterized by clinical, morphologic, and immunohistochemical features.Among 79 cases of PITNKLs from 2008 to 2017 in our institution, 40 (50.63%) were extranodal NK/T-cell lymphoma, nasal type (ENKTL); 32 (40.51%) monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL); 6 (7.59%) intestinal T-cell lymphoma, not otherwise specified; and 1 (1.27%) indolent T-cell lymphoma of the gastrointestinal tract. Small intestine (n = 47) was the most common site. Monomorphic epitheliotropic intestinal T-cell lymphoma showed distinctive clinicopathologic features from other subtypes with high expression (96.88%) of spleen tyrosine kinase (SYK) and PD-L1 (87.5%) and the poorest prognosis (P < .001). CD30 was highly expressed in ENKTL (9/17, 57.94%) and irrelevant to prognosis (P > .05).Cases of PITNKL are biologically heterogeneous; most have a dismal prognosis. SYK and PD-L1 expression might be a significant marker for MEITL and helps differential diagnosis.© American Society for Clinical Pathology, 2024.