[Clinical analysis of 16 cases of pulmonary epithelioid hemangioendothelioma]

Objective: To improve the diagnosis and treatment of pulmonary epithelioid hemangioendothelioma (P-EHE). Methods: Sixteen patients diagnosed with P-EHE in Fuzhou Pulmonary Hospital of Fujian Province from January 2009 to July 2020 were collected. Their gender, age, imaging findings, pathological characteristics, treatment protocols, survival and other clinical data were summarized and analyzed. Results: The ratio of male to female among the 16 patients was 1∶1; and the average age of onset was 47.75 years. Most cases of PEHE (9/16) were found by physical examination, while some cases developed respiratory symptoms such as cough, sputum, shortness of breath, hemoptysis, chest pain, etc. (7/16). In most patients the lesions were localized to the lungs (11/16), while bone metastasis (1/16), lymph node metastasis (1/16), and pleural metastasis (4/16) also occurred. The pathological tissues were obtained mainly through surgical thoracoscopy. Chest CT images showed multiple nodules in both lungs, with most of the nodules less than 2.0 cm in diameter, and calcifications were seen, while solitary nodules and masses were rare, and pleural metastases could be manifested as pleural thickening and pleural effusion. The pathological findings were well-defined eosinophilic nodules with irregularly arranged nest-like structures. Those eosinophilic nodules had few central cells and abundant peripheral cells, which extended into the alveolar cavity like papillae. The tumor cells were epithelioid with small atypia, and vacuoles and red blood cells could be seen in the cytoplasm of individual tumor cells. Immunohistochemically, the tumor cells were positive to CD34, CD31, Factor Ⅷ andvimentin (VIM). Follow-up of 0.5 to 11 years showed that four patients died, two lost to follow-up, and the rest of the patients were in good condition, with a median overall survival (OS) of 4.58 years. Conclusions: PEHE is a rare low-grade lung tumor with no specific clinical manifestations. It can be diagnosed with chest imaging and pathological immunohistochemistry. Moreover, there is currently no standard treatment for PEHE, and most patients have a good prognosis.