ECP 2023 Abstracts

S341 Virchows Archiv (2023) 483 (Suppl 1):S1–S391 13 E-PS-21-012 Epithelioid haemangioendothelioma of the thorax L. Farah*, R. Ayadi, H. Ichrak, B. Emna, O. Ismail, A. Ayadi, S. Hamza *CHU Abderrahmen mami Tunisia, Tunisia Background & objectives: Epithelioid haemangioendothelioma (EHE) is an extremely rare malignant vascular neoplasm. Thoracic EHE involves not only the lungs but also the pleurae, the bones and the mediastinum. The aim of this study is to discuss clinical-pathological characteristics of this tumour. Methods: We report a retrospective study of 8 cases of EHE diagnosed at our department of pathology between 2004 and 2022. Results: There were 3 female and 5 male patients, aged between 38 and 80 years with a mean of 40,5. The diagnosis was made on surgical resec- tion (n=5), mediastinoscopic biopsy (n=2) and liver biopsy (n=1). The histological examination showed nodules with increased cellularity at the periphery and an abundant hypocellular, eosinophilic sclerotic centre. It is composed of infiltrative cords and nests of epithelioid cells within a myxohyaline stroma. Tumour cells have a glassy eosinophilic cytoplasm, uniform ovoid nuclei and inconspicuous nucleoli. Intra-cytoplasmic vacu- oles containing erythrocytes were observed. Some cases were associated with necrosis and mitotic figures (high risk factors). Immunohistochem- istry revealed diffuse positivity with CD34 and CK negative cells. Conclusion: Establishing a diagnosis of EHE is a challenging task, given the rarity of the disease and the large spectrum of symptoms. E-PS-21-013 Pulmonary tuberculosis associated with lung cancer: report of an institutional experience in Northern Tunisia L. Farah*, R. Ayadi, B. Emna, O. Khouildi, A. Ayadi, S. Hamza, H. Ichrak *CHU Abderrahmen mami Tunisia, Tunisia Background & objectives: The simultaneous occurrence of pulmonary tuberculosis and lung cancer has been reported in various case series. But this association is still controversial. The objective of this study is to report our experience in case of coexistence of the two diseases. Methods: We performed a retrospective study involving 65 cases of combined pulmonary tuberculosis and lung cancer diagnosed at our department between 2004 and 2022. Results: There were 61 male and 4 female patients, aged between 43 and 80 years, with a mean of 52, 5. In all cases, tuberculosis was an incident finding, simultaneous to the diagnosis of cancer. Adenocarci- noma was the most common histological type (65%), followed by Squa- mous carcinoma (28%), Neuroendocrine carcinoma (5%) and finally Adenosquamous carcinoma and Lymphoepithelioma-like carcinoma in 1% each. Most of our patients were diagnosed with advanced lung cancer stage IIIA (n=17), followed by Stage IIB (n= 14), Stage IA (n = 13), Stage IIA (n= 4), Stage IB (n = 3) and finally stage IIIB (n= 1). Conclusion: If a coexistence between tuberculosis and lung cancer is possible, the phenomenon remains too rare to sustain the theory of « tumour in the scar ». Nevertheless, this emphasizes the importance of LC screening in pulmonary tuberculosis patients even after the infec- tion is treated. E-PS-21-014 Pulmonary sclerosing pneumocytoma: a histological diagnostic challenge L. Farah*, R. Ayadi, B. Emna, O. Khouildi, H. Ichrak, A. Ayadi, S. Hamza *CHU Abderrahmen mami Tunisia, Tunisia Background & objectives: Sclerosing pneumocytoma is an uncommon benign pulmonary tumour, derived from primitive respiratory epithelium. This neoplasm represents a diagnostic challenge with adenocarcinoma and carcinoid tumours. The aim of this study is to present clinical-path- ological characteristics of these tumours with literature review. Methods: We report a retrospective study involving 3 cases of Scleros- ing pneumocytoma diagnosed at our department of pathology between 2004 and 2022. Results: There were 3 women ranged in age from 32 to 59, with a mean of 54. the tumour presented with multiple formations in two patients, and as a solitary nodule in one patient. The tumour size ranged from 0,1 to 7,5 cm. Histological examination showed solid and papillary architecture with sclerotic stroma. Papillae were lined with two types of cells: cuboidal and round cells. Surface cells are cuboidal, resembling type II pneumocytes. Round cells are polygonal with abundant eosinophilic cytoplasm, oval nuclei, even chromatin and indistinct nucleoli. Immunohistochemical findings revealed positive staining in both cell types for cytokeratin and TTF1. But only round cells expressed positivity for EMA. Conclusion: Sclerosing pneumocytoma is a rare pulmonary tumour. Pathologists should always keep this entity in mind, since its broad spectrum of differential diagnosis makes it a diagnostic pitfall. E-PS-21-015 Utility of bronchoscopic small biopsy samples - experience of one centre in two-year period S. Glumac*, R. Janković, M. Stjepanović, S. Popević, J. Varda, V. Valčić, M. Jovanović *Institute for Pathology, Medical Faculty, University of Belgrade, Serbia Background & objectives: Increasing incidence of lung disease worldwide warrants reevaluation and improvement of diagnostic pro- cedures with optimal celerity and certainty. This study aims to analyse bioptates acquired through small lung biopsies as a form of evaluating them as a diagnostic method. Methods: Pathological reports assessed in this cross-sectional study are from biopsy samples procured at the Pulmonology Clinic of the University Clinical Centre of Serbia, and processed and reviewed at the Institute for Pathology, Medical Faculty, University of Belgrade, during 2021. and 2022. Results: In two year period a total of 1038 reports were reviewed; cytological samples of pleural effusions were excluded. Non-neoplastic pathological conditions were 275 reports, of which sarcoidosis is the most common diagnosed (61/275). Various neoplastic disorders were present in 764 reports. As for primary malignant neoplasms of lung a squamous cell carcinoma was the most common diagnosed (226/764), 222 as adenocarcinoma, 72 as NSCLC NOS, 110 as small cell carci- noma. and 60 metastatic tumours. The average patient age at the time of diagnosis was approximately 67. With the exception of secondary neoplasms, all neoplasms were more prevalent in the male population. Conclusion: Small lung biopsies are a significant part of the diagnostic algorithm and monitoring of both non-neoplastic and neoplastic dis- eases of the lungs, trachea and bronchi. The significance rises by the fact that over two thirds of lung cancers are diagnosed in advanced clinical stage and by small biopsy, as well as that the procured tissue is to be used for future predictive immunohistochemical and molecular testing. E-PS-21-017 The utopia study: ultrafast next-generation sequencing testing in patients with non-small cell lung carcinomas S. Hernandez Prieto*, E. Conde, M. Alonso, M. Veras Lista, A. Illar- ramendi, D. Curto, M. Herrera, H. Bote, J. Baena, J. Zugazagoitia, L. Paz-Ares, F. Lopez-Rios *Pathology Department, Hospital Universitario 12 de Octubre. Research Institute Hospital 12 de Octubre (i+12). Madrid, Spain Background & objectives: Although comprehensive genomic pro- filing is now standard of care for non-small cell lung carcinomas