4例胸膜肺母细胞瘤临床病例分析与文献复习

Clinical analysis and literature review of 4 pleuropulmonary blastoma cases

目的：探索Ⅰ型及Ⅱ型胸膜肺母细胞瘤（pleuropulmonary blastoma,PPB）的临床病理特征、诊断及治疗方法。方法：收集2001年3月至2015年3月湖南省儿童医院PPB病例3例（分别对应本文中例1、2、3）,2015年北京儿童医院会诊复发病例1例（例4）进行综合汇报以及预后追踪。4例患儿中有2名女孩,2名男孩,年龄分布在21~59月之间,起病均为为咳嗽、喘息等非特异性症状,影像学检查提示气胸、肺不张或肺部囊性病变。结果：4例PPB术后均诊断为Ⅱ型PPB,镜下均可见原始胚胎成分及肉瘤样区域混合存在,后者可向横纹肌母细胞或软骨分化。免疫组织化学4例均表达Vimentin和Desmin,2例表达良性上皮CK-pan和Myogenin,1例表达p53;例4初次术后切片复诊结果为Ⅰ型PPB,镜下仅在良性纤毛柱状上皮见散在分布的横纹肌母细胞及较多小圆形细胞,免疫组化表达CK-pan、Vimentin及Myogenin。结论：儿童PPB罕见,镜下以原始胚胎及肉瘤成分混合存在为特征,Ⅰ型PPB肿物大体形态及镜下均具有迷惑性,需加强取材避免过低诊断。

Objective： To explore the clinicopathological features, diagnosis and treatment of type Ⅰ and type Ⅱpleuropulmonary blastoma（PPB）. Methods： Selected 3 PPB cases collected from the Hunan Children＇s Hospital in a period from March 2001 to March 2015（corresponding to sample 1, 2 and 3 in this paper, respectively） and 1 consultation recurrence case from the Beijing Children＇s Hospital in 2015（corresponding to sample 4）. Subsequently, a comprehensive analysis and a prognosis tracking result were reported based on these 4 cases, including 2 girls and 2 boys, and the age ranged from 21 to 59 months. All the 4 cases originated from nonspecific symptoms, such as cough and wheezy; and the imaging examinations showed pneumothorax, atelectasis or pulmonary cystic lesions. Results： All 4 cases were diagnosed as type Ⅱ PPB with the original embryonic compositions mixed with sarcomatoid regions, which can differentiate into rhabdomyoblasts or cartilage, under microscope. Immunohistochemically, Vimentin and Desmin were all expressed, Myogenin and CK-pan under benign epithelial expressed in 2 cases, and p53 in only 1 case. Sample 4 was diagnosed as type Ⅰ PPB after the first surgery, under the microscope rhabdomyoblasts and small round cells were distributed on the benign ciliated columnar epithelium, and the immunohistochemical test expressed CK-pan, Vimentin and Myogenin. Conclusion： PPB is rare in children and characterized by the original embryonic compositions mixed with sarcomatoid regions under microscope. As type Ⅰ PPB shows confusing features in both morphology and microscope, thus we need more biopsy tissue to avoid underestimates.