假内分泌肉瘤（PES）是最近描述的一种肿瘤，通常发生在椎旁软组织中。在组织学上，PES 类似于分化良好的神经内分泌肿瘤，但缺乏上皮/神经内分泌标志物的表达，并且大多数显示异常的核 β-连环蛋白阳性。我们描述了一种 PES 的临床病理学和分子特征以及 DNA 甲基化谱。一名 52 岁男性切除的椎旁软组织肿块显示神经内分泌样肿瘤，角蛋白和突触素呈阴性，并显示弥漫性核 β-连环蛋白表达。靶向 NGS 证实了 CTNNB1 (p.S37C) 突变。全基因组甲基化分析显示与中枢神经系统肿瘤（版本 11b6 和 12b6）或肉瘤分类器（校准分数≤0.3）中的任何甲基化类别都不匹配，但与最近报道的 PES 聚类在一起，其中也进行了甲基化分析。手术后 18 个月内，他一直保持无病状态，随后又进行了放化疗。随着对更多病例的检查，我们的研究结果表明 PES 可能具有独特的甲基化分析特征。© 2023。作者获得 Springer-Verlag GmbH 德国（Springer Nature 旗下公司）的独家许可。

Pseudoendocrine sarcoma (PES) is a recently described neoplasm typically arising in paravertebral soft tissues. Histologically, PES resembles well-differentiated neuroendocrine tumors but lacks expression of epithelial/neuroendocrine markers, and most show aberrant nuclear β-catenin positivity. We describe the clinicopathological and molecular features and DNA methylation profile of one PES. A resected paraspinal soft tissue mass in a 52-year-old man showed a neuroendocrine-like neoplasm, negative for keratin, and synaptophysin and showing diffuse nuclear β-catenin expression. Targeted NGS confirmed a CTNNB1 (p.S37C) mutation. Whole genome methylation analysis showed no match to any methylation class in the central nervous system tumor (versions 11b6 and 12b6) or sarcoma classifier (calibrated scores of ≤0.3), but clustered together with a recently reported PES in which methylation analysis was also performed. He remained disease-free for 18 months after surgery, followed by chemoradiation. As more cases are examined, our findings suggest that PES may have a unique methylation profiling signature.© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.