Department of Pathology, MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA.
Lung. 2012 Dec;190(6):677-83. doi: 10.1007/s00408-012-9405-9. Epub 2012 Jul 17.
The clinicopathological and immunohistochemical features of six primary pulmonary primitive neuroectodermal tumors (PNETs) are reported.
The patients were four men and two women aged 22-56 years (mean = 32.3 years). The main presenting symptoms included chest pain, shortness of breath, and cough. The tumor size ranged from 4 to 9.6 cm.
Macroscopically, the tumors were circumscribed, yellow-white in color, and of soft and friable consistency. Histologically, the lesions were composed of a monomorphic population of solidly packed round cells with a round-to-ovoid nucleus, fine chromatin, small nucleoli, and scanty pale cytoplasm. Immunohistochemically, the tumor cells were uniformly positive for CD99, neuron-specific enolase, and vimentin, and single cases focally expressed cytokeratin and S100. Fluorescence in situ hybridization analysis performed in two cases showed positive rearrangement for the EWSR1 gene at the 22q12 locus. Follow-up information available for four patients showed that three had died 24-54 months after diagnosis and one patient is alive 11 months after diagnosis. Two patients were lost to follow-up.
Primary PNETs of the lung are rare tumors that need to be added to the differential diagnosis of primary pulmonary neoplasms composed of small cells. Awareness of this entity as a primary pulmonary neoplasm is required in order to avoid misdiagnosis and unsuitable treatment of patients.
本文报道了 6 例原发性肺原始神经外胚层肿瘤（PNET）的临床病理和免疫组织化学特征。
患者为 4 男 2 女，年龄 22-56 岁（平均 32.3 岁）。主要表现为胸痛、呼吸困难和咳嗽。肿瘤大小 4-9.6cm。
大体上，肿瘤边界清楚，呈黄白色，质软易碎。组织学上，病变由形态单一的实性圆形细胞组成，细胞核呈圆形至卵圆形，染色质细，核仁小，胞质淡染。免疫组化肿瘤细胞均弥漫表达 CD99、神经元特异性烯醇化酶和波形蛋白，个别病例局灶性表达细胞角蛋白和 S100。2 例进行荧光原位杂交分析显示 EWSR1 基因在 22q12 位点发生阳性重排。4 例患者的随访信息显示，3 例患者在诊断后 24-54 个月死亡，1 例患者在诊断后 11 个月仍存活。2 例患者失访。
原发性肺 PNET 是一种罕见的肿瘤，需要纳入由小细胞组成的原发性肺肿瘤的鉴别诊断。为避免误诊和对患者进行不适当的治疗，需要认识到这是一种原发性肺肿瘤。
