ECP 2022 Abstract Book

Virchows Archiv (2022) 481 (Suppl 1):S1–S364 13 comparability and would yield valuable results of ancillary studies ( IHC and molecular tests) as well as an excellent archival material. This is highly significant due to the increasing number of tests with direct impact on targeted therapy, in the personalized medicine. PS-11-019 Cervical atrophy as a pitfall for cytological diagnosis: a 5-year study from a tertiary centre in Lisbon M. Pinho*, R. Moiteiro da Cruz, T. André Sousa Oliveira, J. Boav- ida, R. Luís *Department of Pathology - Hospital de Santa Maria, CHULN; Faculdade de Medicina da Universidade de Lisboa, Portugal Background & objectives: Atrophy is a well-documented diagnostic pitfall for squamous cell lesions in cervical cancer screening in peri- and post-menopausal women. This study aims to evaluate the screening accuracy in women aged 45-years or older to determine whether aging affects cytological interpretation. Methods: We reviewed all cervical cytology reports, spanning through 2017-2021 and pertaining to women ≥45 years. A cor- relation of Bethesda categories of “Negative for Intraepithelial Lesion/Malignancy’’ (NILM) with reported atrophy, “Atypical Squamous Cells cannot exclude high-grade” (ASC-H) and “High- grade Squamous Intraepithelial Lesion” (HSIL) with subsequent histological studies were performed. High-risk HPV co-testing results (Cobas®) were additionally recorded. Results: A total of 226 cytological diagnoses and matched histo- logical evaluations (taken simultaneously or up to 24 months prior) were assessed. In instances with multiple tissue specimens, the higher-grade diagnosis was recorded; samples insufficient for diag- nosis were excluded. The risk of malignancy (ROM) ranged from 13.1% to 80.6% in negative and positive categories, respectively; the performance analysis revealed a sensitivity of 93.0%, a speci- ficity of 62.4%, a positive predictive value of 80.6% and a negative predictive value of 86,9%. When intraepithelial lesion was present, HPV-16 was detected in 29.5% and HPV-18 in 3.6% of cases. Conclusion: Overall, as a cervical cancer screening, cytology shows a good sensitivity with a lower specificity, as expected. Although Bethesda criteria accurately define atrophy, it is important to be aware that these benign changes can lead both to overdiagnosis, mostly by overvaluing slight changes, and underdiagnosis, by dismissing cytological atypia. PS-11-020 Added value of cell block over liquid-based cytology alone in the diagnosis of non-necrotizing lymphadenopathy on endo- scopic ultrasound–guided-transbronchial needle aspiration of mediastinal lymph nodes for sarcoidosis investigation C. Saglietti*, E. Hewer *Institute of Pathology, Lausanne University Hospital, Switzerland Background & objectives: Endoscopic ultrasound–guided-transbron- chial needle aspiration (EBUS-TBNA) for sarcoidosis investigation can be evaluated by conventional cytology, liquid-based cytology (LBC) and cell block (CB), with few data published about their performance. We reviewed our case history for discordant results between CB and LBC. Methods: We reviewed all of the cases addressed over the last year for investigation of mediastinal lymphadenopathy with suspicion of sarcoidosis, for which patients had signed the general consent for research in our institution. We identified four patients who had undergone EBUS-TBNA. All of them were also investigated by bronchoalveolar lavage (BAL). Flow cytometry was performed on BAL with lymphocytosis. Results: We recovered 4 patients (4 males; mean age: 50 years) with a total of 9 TBNAs of mediastinal lymph nodes. For all of the TBNAs, no granuloma was observed on LBC slides (in two cases, only histiocytes were present). CB was done for 8/9 TBNA (89%); in 7/8 cases (88%), granulomas were seen on the CB in the absence of necrosis, thus leading to the diagnosis of non-necrotizing lymphadenopathy in 4/4 patients. On BAL, two patients showed lymphocytosis with mildly increased CD4+/ CD8+ (3.9 and 3.08; reference range: 1.3–3). Conclusion: The addition of CB in the processing of EBUS-TBNA performed in the context of sarcoidosis investigation in patients with mediastinal lymphadenopathy can help to detect the presence of granulomas, which may otherwise not be present on LBC slides. As not all laboratories routinely perform CB in tandem with LBC preparations, this may represent a diagnostic pitfall. We therefore recommend that a CB be performed on EBUS-TBNA in this par- ticular context. PS-11-021 Random rescreening 10% of negative cervicovaginal smears: method for quality assurance F. Ozden* *Department of Pathology, Istanbul Medipol University, Turkey Background & objectives: Laboratories use different methods of quality assurance for cervicovaginal smears. Random rescreening of %10 of negative gynaecologic smears is one of the effective methods for decreasing false negativity. In this study, we presented our single- institution data. Methods: All negative gynaecologic smears diagnosed over 29 months are included in this study. We plan the review of the smears weekly. We randomly select 10% of negative smears and distribute them crosswise among pathologists. If any discrepancy occurs between primary and secondary screeners, we try to reach a consensus on the diagnosis by including tertiary or quaternary assessments. Results: Twenty-eight thousand five hundred twelve smears were negative, and 10% were rescreened between November 1, 2019, and March 31, 2022. Of these rescreened ones, sixteen of them were evaluated as false negatives. Eleven were reported as atypical squamous cells of undetermined significance (ASC-US), four as low-grade squamous intraepithelial lesion (LSIL), and one as adenocarcinoma. Conclusion: Random rescreening 10% of negative smears can effectively improve laboratory performance and decrease false- negative numbers. Unlike other studies and practices, we do not sign out reports of these selected smears that will be rescreened and wait for the consensus if any discrepancy occurs. So this study can be considered not a retrospective study but rather a prospective practice of our institution. PS-11-022 HPV-based opportunistic cervical cancer screening in Barce- lona. Preliminary results in >30 year old women J. Lop Gros*, B. Lloveras, G. Bosch, A. Quiñonero, L. Serrano, A. Buron, M.A. Agüero, J.M. Solé *Hospital del Mar, Spain Background & objectives: Cervical cancer screening using HPV detection as the primary test is being implemented in Barcelona in S127