Yin Jing, Wang Shoufeng, Zheng Mo
Department of Pathology, Tianjin Fifth Central Hospital Tianjin, China.
Int J Clin Exp Pathol. 2021 Oct 15;14(10):1056-1060. eCollection 2021.
Malignant Peripheral Nerve Sheath Tumor (MPNST) is a malignant mesenchymal tumor. The majority of MPNSTs are found in patients with neurofibromatosis type 1 (NF-1) who have a high-grade sarcoma. At the moment, there are just a few instances of low-grade MPNST caused by NF-1. We present a case of malignant transformation of NF-1 into low-grade MPNST in a patient with a long history of the disease. Multiple protruding masses with ulceration on the right shoulder and chest wall were discovered during physical examination. Complete tumor excision was done, followed by hematoxylin-eosin and immunohistochemical staining. A portion of the tumor had higher cellularity, hyperchromatic cell nuclei, and mitoses were seen in only five out of ten high-power fields. S-100 and vimentin were positive, whereas cytokeratin, desmin, SMA, and CD34 were negative. Ki-67 (MIB1) labeling index hot-spotting was around 25%. This was thought to be NF-1 malignant transformation into low-grade MPNST. Overall, knowing the clinical and pathologic characteristics of the disease, plus growing knowledge or experience with the condition, may improve preoperative diagnostic accuracy and extending survival time.
恶性外周神经鞘膜瘤（MPNST）是一种恶性间叶组织肿瘤。大多数MPNST见于1型神经纤维瘤病（NF-1）患者，这些患者患有高级别肉瘤。目前，由NF-1引起的低级别MPNST病例较少。我们报告一例患有该疾病多年的患者，其NF-1恶变为低级别MPNST。体格检查发现右肩部和胸壁有多个伴有溃疡的突出肿块。进行了肿瘤完整切除，随后进行苏木精-伊红染色和免疫组化染色。肿瘤的一部分细胞密度较高，细胞核深染，在十个高倍视野中仅在五个视野中可见有丝分裂。S-100和波形蛋白呈阳性，而细胞角蛋白、结蛋白、平滑肌肌动蛋白和CD34呈阴性。Ki-67（MIB1）标记指数热点约为25%。这被认为是NF-1恶变为低级别MPNST。总体而言，了解该疾病的临床和病理特征，以及增加对该疾病的认识或经验，可能会提高术前诊断准确性并延长生存时间。
