Department of Pathology, Jinhua Municipal Central Hospital, 351 Mingyue Road, Jinhua, 321000, Zhejiang Province, People's Republic of China.
Department of Pathology, the People's Hospital of Changfeng County, Changfeng County, Anhui Province, People's Republic of China.
Diagn Pathol. 2020 Feb 10;15(1):15. doi: 10.1186/s13000-020-00930-2.
Primary pulmonary myxoid sarcoma (PPMS) is an extremely rare lung sarcoma that is characterized in most cases by recurrent balanced chromosomal translocation t(2;22)(q33;q12) leading to the oncogenic fusion gene EWSR1-CREB1.
We report a case of PPMS with molecular confirmation using fluorescence in situ hybridization (FISH) and DNA sequencing in a 45-year-old female patient. Computer tomography (CT) scanning revealed a peripheral circumscribed solid mass of 2.1 × 2 cm in the right lung superior lobe. Histologically, the tumor cells ranged from stellate, polygonal to chondrocyte-like or physaliferous-like, forming reticular network of delicate lace-like cellular strands and cords in abundant myxoid stroma. The tumor cell immunophenotype was positive for vimentin, EMA and negative for CK-pan, TTF-1, CAM5.2, S-100, calponin, SMA, desmin, ALK, CD31 and CD34. Molecular analysis demonstrated EWSR1-CREB1 gene fusion in this tumor. During 38 months of follow-up, the patient was alive with no clinical or radiological evidence of recurrence or metastasis.
PPMS is a rare low-grade sarcoma with distinct histological and genetic features. We add another case to the literature of this rare tumor and report for the first time occurrence of chondrocyte-like and physaliferous-like tumor cells in this tumor, thus enriching its morphologic and cytologic spectrum.
原发性肺黏液样肉瘤（PPMS）是一种极为罕见的肺肉瘤，大多数情况下以反复出现的平衡染色体易位 t(2;22)(q33;q12)为特征，导致致癌融合基因 EWSR1-CREB1。
我们报告了一例经荧光原位杂交（FISH）和 DNA 测序分子证实的 PPMS 病例，患者为 45 岁女性。计算机断层扫描（CT）显示右肺上叶有一个 2.1×2cm 的周围边界清楚的实性肿块。组织学上，肿瘤细胞呈星状、多边形、软骨样或泡状，在丰富的黏液样基质中形成网状的纤细花边状细胞条索和索带。肿瘤细胞免疫表型为波形蛋白阳性，EMA 阴性，CK-pan、TTF-1、CAM5.2、S-100、钙调蛋白、SMA、结蛋白、ALK、CD31 和 CD34 阴性。分子分析显示该肿瘤存在 EWSR1-CREB1 基因融合。在 38 个月的随访期间，患者存活，无复发或转移的临床或影像学证据。
PPMS 是一种罕见的低度肉瘤，具有独特的组织学和遗传学特征。我们在该罕见肿瘤的文献中增加了另一个病例，并首次报道了该肿瘤中存在软骨样和泡状肿瘤细胞，从而丰富了其形态和细胞学谱。
