Lau Patrick P L, Wong On-Kit, Lui Philip C W, Cheung Oi-Yee, Ho Luen-Cheung, Wong Wing-Cheuk, To Ka-Fai, Chan John K C
Department of Pathology, Queen Elizabeth Hospital, Hong Kong, SAR China.
Am J Surg Pathol. 2009 Nov;33(11):1666-72. doi: 10.1097/PAS.0b013e3181aec307.
Myopericytoma is an uncommon, benign perivascular myoid cell tumor that occurs almost exclusively in somatic soft tissues. We report 2 cases occurring in patients with acquired immunodeficiency syndrome who show unusual clinical and biologic features. One patient presented with a bronchial mass and the other developed mass lesions of the tongue, vocal cord, and brain. Histologically, oval to plump spindly tumor cells with uniform nuclei and scanty cytoplasm formed sheets or cuffs around gaping or narrow vascular spaces. Focally, these areas merged into fascicles of more elongated cells with eosinophilic cytoplasm. The tumor cells were immunoreactive for actin but not desmin, and showed uniform labeling for Epstein-Barr virus (EBV) encoded RNAs on in-situ hybridization. Both patients were alive 5 years after incomplete excision of the lesions. In conjunction with another case reported in the literature, myopericytoma occurring in acquired immunodeficiency syndrome patients exhibits several features distinct from sporadic myopericytoma: presentation in anatomic sites other than somatic soft tissues, frequent presence of multifocal disease, and association with EBV. This tumor type therefore also broadens the spectrum of neoplasms associated with EBV.
肌周细胞瘤是一种罕见的良性血管周围肌样细胞肿瘤，几乎仅发生于体部软组织。我们报告2例发生于获得性免疫缺陷综合征患者的病例，这些病例具有不寻常的临床和生物学特征。1例患者表现为支气管肿物，另1例患者出现舌、声带和脑部的肿物病变。组织学上，椭圆形至饱满的梭形肿瘤细胞，核均匀，胞质稀少，围绕宽大或狭窄的血管间隙形成片状或套状结构。局部区域，这些区域融合成由更多伸长细胞组成的束状结构，胞质嗜酸性。肿瘤细胞肌动蛋白免疫反应阳性，但结蛋白免疫反应阴性，原位杂交显示对爱泼斯坦-巴尔病毒（EBV）编码RNA呈均匀标记。2例患者在病变不完全切除后5年仍存活。结合文献报道的另一例病例，发生于获得性免疫缺陷综合征患者的肌周细胞瘤表现出与散发性肌周细胞瘤不同的几个特征：发生于体部软组织以外的解剖部位、多灶性疾病常见以及与EBV相关。因此，这种肿瘤类型也拓宽了与EBV相关的肿瘤谱。
