Department of Pathology & Laboratory Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, USA.
Robert J. Tomsich Pathology and Laboratory Medicine Institute, Cleveland Clinic, Cleveland, OH, USA.
Int J Surg Pathol. 2023 Aug;31(5):721-727. doi: 10.1177/10668969221120780. Epub 2022 Sep 15.
Well-differentiated/dedifferentiated liposarcoma (WDLPS/DDLPS) represent a significant number of sarcomas arising within the paratesticular region. DDLPS is notorious for a broad histologic spectrum, but epithelioid morphology is rare. Herein, we describe a unique case of paratesticular DDLPS with prominent epithelioid features and molecular confirmation. The patient is 71-year-old-male who presented with multiple paratesticular masses. Morphologic review of the resection specimen revealed a biphasic adipocytic neoplasm consistent with DDLPS. Additionally, epithelioid foci with acinar and nested architecture and focal keratin expression were noted. These areas raised the possibility of a secondary neoplasm including sex cord stromal tumor, germ cell tumor, and paraganglioma. However, MDM2 immunohistochemistry and FISH showed these areas to express MDM2 and exhibit amplification, respectively, confirming that they represented a component of DDLPS. This case further highlights the morphologic diversity of DDLPS as well as the utility of MDM2 studies.
高分化/去分化脂肪肉瘤（WDLPS/DDLPS）是一类常见的发生于腹膜后区域的肉瘤。DDLPS 的组织学形态具有广泛的特征，但上皮样形态较为罕见。在此，我们描述了一例具有显著上皮样特征的独特的腹膜后 DDLPS 病例，并通过分子检测进行了确认。该患者为 71 岁男性，表现为多个腹膜后肿块。切除标本的形态学复习显示为具有双相脂肪性的肿瘤，符合 DDLPS 的特征。此外，还观察到上皮样灶，具有腺样和巢状结构，并伴有局灶性角蛋白表达。这些区域提示可能为继发性肿瘤，包括性索间质肿瘤、生殖细胞瘤和副神经节瘤。然而，MDM2 免疫组化和 FISH 显示这些区域表达 MDM2 并分别表现出扩增，分别确认了它们是 DDLPS 的组成部分。该病例进一步强调了 DDLPS 的形态多样性以及 MDM2 研究的实用性。
