ECP 2022 Abstract Book

Virchows Archiv (2022) 481 (Suppl 1):S1–S364 13 6000 instrument. Short genomic variants (both germline and somatic) and copy-number alterations were detected using stand- ard bioinformatical protocols. Comparison of the germline muta- tion allele frequencies with the 1000 genomes project and the non-Finnish European population of the gnomAD database was performed. Results: Canonical BC-associated genes with pathogenic ger- mline mutations were CHEK2 and ATM. Most of the detected somatic short variants were SNPs and on average only 8% and 6% of them were deletions or insertions. The ratio of tumours har- bouring pathogenic somatic variants in the most affected genes were: KMT2C (31%), MUC4 (34%), PIK3CA (18%) and TP53 (34%). Among the cancer-related genes, copy-number alterations were most common in NBN, RAD51C, BRIP1 and CDH1. COS- MIC mutational signature analysis showed domination of the mutational processes associated with homologous recombination defect (specifically SBS3 was present in 59% of the patients with a weight of 8% or larger), APOBEC-related processes and general aging-related, clock-like signatures. Conclusion: Most of the observed germline mutations are approximately as frequent in the Hungarian BC cohort as in independent European populations. We foresee that more accurate and reproducible detection of pathogenic SNPs and mutations will generate a more complete picture of the landscape of breast carcinomas. Additional investigation of the genes presented above with pathogenic germline mutations and harbouring pathogenic somatic variants and associated pathways could delineate biological susceptibilities and improve treatment options in different breast carcinoma subtypes. PS-MD-01-005 Learnings from two years of external quality assessment (EQA) for BRCA1/BRCA2 testing in metastatic castration- resistant prostate cancer (mCRPC) V. Williams*, J.A. Fairley, M. Woodcock, M.H. Cheetham, N.L. Wolstenholme, Z.C. Deans, S.J. Patton *EMQN, United Kingdom Background & objectives: Prostate cancer is the second most com- mon cancer diagnosis in men. PARP inhibitors were approved for treat- ment of mCRPC patients with BRCA1/BRCA2 gene variants in 2020. We share findings from EQA schemes in which up to 100 laboratories participated globally. Methods: EMQN CIC and GenQA provided three formalin fixed paraffin embedded (FFPE) samples to participating laboratories for BRCA1/BRCA2 testing; the laboratories were asked to use their routine test methodologies. The anonymised results were assessed and peer reviewed. Individual laboratory and overall summary scheme reports were produced to help laboratories improve their performance and to enable benchmarking of results and reporting. Results: Two pilot EQA schemes for BRCA1/BRCA2 testing in Prostate cancer ran in 2020 (32 laboratories) and 2021 (100 labo- ratories). The overall analytical (genotyping) error rate in 2021 was 9%, with errors reported for all three cases, probable causes for these errors will be discussed. Additionally, there were sev- eral common themes identified where improvements could be made to the reporting of the clinical interpretation of the results. Conclusion: The results demonstrate the benefit of participa- tion in EQA to proactively identify sources of error in BRCA1/ BRCA2 genotyping and to improve the quality of interpretation and reporting of results in order to help ensure correct access to treatment and appropriate follow up for mCRPC patients. E-Posters E-PS-01 | E-Posters Autopsy Pathology E-PS-01-001 Ultrasound-guided minimally invasive autopsy as an alterna- tive to conventional autopsy in selected patients: a case report C. Fuente-Díaz*, M. García-Martínez, M. Berríos-Hernández, M.d.l.P. González-Gutiérrez, V. Blanco-Lorenzo, E. Colado, C. González del Rey-Rodríguez, J.R. Riera, A. Encinas-Muñiz *Hospital Universitario Central de Asturias, Spain Background & objectives: Ultrasound-guided Minimally Invasive Autopsy (US-MIA) has been made in the context of COVID-19 pan- demic to reduce the risk of infection during the procedure, but this technique could be used in other autopsies for different purposes. Methods: We report a case of an 85-year-old woman with solid lesions in right-orbital region and both parotids, as well as multiple cervical lymphadenopathies. A previous diagnosis of an aggressive marginal B-lymphoma was made; but the scarce tissue received, did not allow the performance of complementary studies in view of certain clinical discrepancies. Patient died and an autopsy study was requested. Results: Ultrasound Guided Fine Needle Aspiration (US-FNA) and core needle biopsy (CNB) of orbital and parotid lesions were performed with subsequent Rapid On-Site Evaluation -ROSE- of tissue to ensure an adequate specimen and preserve the anatomical appearance. US-MIA made by trained pathologist is a good method to obtain representative tissue samples as an alternative to a conventional autopsy in some patients. In this case, dissection of both parotids would have been a disfiguring and difficult procedure, even unnecessary. This method allowed us to evaluate the specimen on site to guarantee enough material for additional studies and postmortem diagnosis. Conclusion: US-MIA, US-FNA and CNB are safety and easy methods of obtaining tissue samples that can be performed by a trained pathologist. These procedures could be applied in our daily work as an alternative to complete diagnostic autopsies, not only in procedures with elevated risk of infection. E-PS-01-002 Sudden cardiac death in pancreatic acinar-neuroendocrine carcinoma A. Sapargaliyeva*, I. Sergeyeva *Pathology Bureau of Almaty City; Al-Farabi Kazakh National University (Department of Fundamental Medicine), Kazakhstan Background & objectives: Pancreatic acinar-neuroendocrine carci- noma is a tumour that often remains undiagnosed during life. We pre- sent a case of pancreatic acinar-neuroendocrine carcinoma, which was a histological finding in a patient who died from massive myocardial necrosis. Methods: Patient N. (80 years of age) was admitted to the emer- gency hospital with severe chest pain, which was relieved by drugs. Based on clinical signs and the results of laboratory and instru- mental studies, doctors diagnosed infarction of the lateral wall of the left ventricle. The patient died 3 days after admission to the emergency hospital. Results: Autopsy revealed: 1) necrosis in the myocardium, similar to an anterior transmural infarction with involvement of the septal wall; 2) intact coronary artery; 3) myocardial hypertrophy (where LV wall thickness constituted 1.8 cm), thickening of the interven- tricular septum thickness (1.7 cm). S186