关键词: 硬化性肺细胞瘤, 硬化性血管瘤, 不典型, 临床病理特征, 免疫表型, 转移, 预后

Abstract: Objective To study the immunophenotype and clinical pathological significance of pulmonary 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 manifestations 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 manifestations 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 malignant progression needs further research.

Key words: pulmonary sclerosing pneumocytoma, pulmonary sclerosing hemangioma, atypical, clinical pathological characteristics, immunophenotype, transfer, prognosis