PT - JOURNAL ARTICLE AU - Tatyana Novitskaya AU - Ivetta Dvorakovskaya AU - Boris Ariel AU - Lyudmila Novikova AU - Sergey Bugrov TI - Epithelioid hemangioendothelioma of the lungs: 24 cases AID - 10.1183/13993003.congress-2021.PA2185 DP - 2021 Sep 05 TA - European Respiratory Journal PG - PA2185 VI - 58 IP - suppl 65 4099 - http://erj.ersjournals.com/content/58/suppl_65/PA2185.short 4100 - http://erj.ersjournals.com/content/58/suppl_65/PA2185.full SO - Eur Respir J2021 Sep 05; 58 AB - Epithelioid hemangioendothelioma of the lungs (EHL) is a multifocal formation with a low grade of malignancy. It is more common in women aged 12-60 years. The etiology and pathogenesis of EHL are unknown, the possibility of a genetic predisposition is not excluded.Aims: To study the clinical and histological features of EHL.Material and methods: We studied 24 EHL removed from 23 women and 1 man aged 15-61 years (average age 39.9 years). In all cases, EHL was detected by chance during preventive examinations. On tomograms multiple dense formations with smooth contours were revealed. Histological and immunohistochemical methods were used: H&E, picrofuchsin, alcian blue, PAS reaction, detection of expression of CD 31, CD 34. Tumors are rounded, dense, gray-white, with clear boundaries.Results: Histological examination revealed round nodules in all EGL, in which 3 zones are distinguished. The central zone is a cell-free hyalinized connective tissue. The intermediate zone contains homogeneous substance and a small amount of tumor cells in a rounded gaps. The outer area of multicellular organisms, cells of the polymorphic form, making a small group in a myxoid stroma. Capillaries, vascular kidneys, and minor lymphoid infiltration are detected. Tumor masses are found in the lumen of the arteries and veins.In the areas of cell proliferation, the expression of CD31 and CD34 is detected, which decreases as the deposit accumulation level.Conclusion: The differential diagnosis is carried out with granulomatosis, hamartoma, sclerosing hemangioma, metastatic lung damage. The expression of CD31 and CD34 confirms the histogenetic relationship of the cells with the polypotent stem vascular cell. The forecast is unpredictable.FootnotesCite this article as: European Respiratory Journal 2021; 58: Suppl. 65, PA2185.This abstract was presented at the 2021 ERS International Congress, in session “Prediction of exacerbations in patients with COPD”.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).