伴不典型临床病理特征的硬化性肺细胞瘤

Pulmonary sclerosing pneumocytoma with atypical clinical and pathological features

目的研究伴不典型临床病理特征的硬化性肺细胞瘤(PSP)/硬化性血管瘤(PSH)的免疫表型及临床病理学意义。方法按入组要求筛选病例,收集15例伴不典型临床病理特征的PSP/PSH患者的临床病理资料,回顾性分析患者的大体及镜下改变、免疫组化表达特点、临床及影像学表现,高通量测序检测1例发生同时性区域淋巴结转移的硬化性肺细胞瘤的基因突变情况。结果伴不典型临床病理特征的PSP多见于中年女性,年龄33⁃73岁,中位年龄为54岁,多位于左上肺和右下肺,大多数患者无症状,由体检时发现,影像学多表现为孤立性圆形或类圆形肿块,边界清。HE染色的特征性表现为4种组织结构(乳头区、硬化区、实性区、血管瘤样区)以及2种细胞(表面细胞、间质细胞)构成,免疫组化(IHC)染色的两种细胞均表达EMA、TTF⁃1,另外表面细胞表达CK7、NapsinA,间质细胞表达Vim,不表达CK7、NapsinA。15例中有1例发生同时性区域淋巴结转移,随访10个月,目前该患者生存良好,无复发及远处转移。结论伴不典型临床病理特征的硬化性肺细胞瘤的临床表现及影像学特征无明显特异性,组织学形态具有多样性,术中冰冻误诊或延迟诊断率高,诊断时不仅要掌握HE特征性表现及IHC表达特点,还应关注其是否存在恶性生物学行为。另外,15例中有1例发生同时性区域淋巴结转移,但未出现AKT1 E17K体细胞突变和TP53 C176Y胚系突变,该例患者发生恶性进展的原因有待进一步研究。

Objective To study the immunophenotype and clinical pathological significance of pulmo⁃nary sclerosing pneumocytoma(PSP)/sclerosing hemangioma(PSH)with atypical clinical and pathological features.Method Cases were selected according to enrollment requirements,and clinical and pathological data of 15 PSP/PSH patients with atypical clinical and pathological features were collected.The gross and microscopic changes,immunohistochemical expression characteristics,clinical and imaging manifesta⁃tions of the patients were retrospectively analyzed.High throughput sequencing was performed to detect gene mutations in one case of pulmonary sclerosing pneumocytoma withsimultaneous regional lymph node metastasis.Results PSP with atypical clinical and pathological features was more common in middle⁃aged women,ranging from 33 to 73 years old,with a median age of 54 years old.It was mostly found in the left upper and right lower lungs,and most patients were asymptomatic.During physical examination,it was found that the imaging findings were mostly solitary circular or quasi circular masses with clear boundaries.The characteristic manifestation of HE is composed of four organizational structures(papillary area,sclerotic area,solid area,and hemangioma like area)and two types of cells(surface cells,interstitial cells).Both types of IHC cells express EMA and TTF⁃1,while surface cells express CK7,NapsinA,interstitial cells express Vim,without CK7,NapsinA.Among the 15 cases,1 case experienced simultaneous regional lymph node metastasis and was followed up for 10 months.Currently,the patient has survived well without recurrence or distant metastasis.Conclusion The clinical manifes⁃tations and imaging features of PSP with atypical clinical and pathological features are not significantly specific,and the histological morphology is diverse.The misdiagnosis or delayed diagnosis rate during surgery is high.When diagnosing,it is not only necessary to grasp the characteristic HE manifestations and IHC expression characteristics,but also to pay attention to whether it has malignant biological behavior.In addition,1 out of 15 cases had simultaneous regional lymph node metastasis,but there was no AKT1 E17K somatic mutation and TP53 C176Y germline mutation.The reason why this patient develop malig⁃nant progression needs further research.