ECP 2023 Abstracts

S77 Virchows Archiv (2023) 483 (Suppl 1):S1–S391 13 that were successfully analysed. INSM1 positivity occurred in 59 non- neuroendocrine tumour entities, of which 15 entities contained at least one strongly positive case. Comparison with synaptophysin and chro- mogranin A revealed that in NEN, synaptophysin showed the highest sensitivity (93.3%), followed by INSM1 (89.2%) and chromogranin A (87.5%). In neuroendocrine carcinomas (NEC), sensitivity was highest for INSM1 (88.0%), followed by synaptophysin (86.5%) and chromogra- nin A (66.4%). The additional use of INSM1 increased the sensitivity for detecting neuroendocrine differentiation in NEN from 88.2% (synap- tophysin and chromogranin A) to 91.2% (synaptophysin, chromogranin A and INSM1). Conclusion: Our study shows that INSM1 is a useful additional marker for neuroendocrine differentiation that shows a particularly high sensitivity in NEC. The additional use of INSM1 results in a higher sensitivity for the identification of a neuroendocrine differen- tiation than what can be obtained by using only synaptophysin and chromogranin A. PS-07-005 PD-L1 IHC 22C3 pharmDx: real time study for stained slide stability on multiple tumour types D. Moquin*, S. Tabuena-Frolli, S. Hund, L. Peltz, M. Adams, J. Vasquez, G. Toland, B. Watts, K. Kersch, M. Kalpakoff *Agilent Technologies, Inc., USA Background & objectives: PD-L1 22C3 IHC pharmDx (SK006) is a qualitative immunohistochemical (IHC) assay to detect PD-L1 expres- sion in formalin-fixed, paraffin-embedded (FFPE) tissues. Studies have been conducted to evaluate the stability of the PD-L1 IHC 22C3 pharmDx stain on multiple FFPE tumour types. Methods: Slides stained using PD-L1 IHC 22C3 pharmDx from 10 different tumour types were aged in the dark at ambient temperature and assessed at pre-determined time intervals. Slides were blinded, randomized, and scored using Combined Positive Score (CPS). Slides stained at time zero (T0) were used as reference for remaining time points. Each tumour type was studied and analysed separately. Results: Stability was determined using regression analysis and was based on the specimen in the cohort exhibiting the shortest stability. Analysis performed on CPS results indicated the follow- ing stained slide stabilities for each tumour type when stored in the dark at ambient temperature: 810 days for Urothelial Carcinoma (UC), 550 days for Gastric Carcinoma (GC), 735 days for Triple- negative Breast Cancer (TNBC), 763 days for Head and Neck Squa- mous Cell Carcinoma (HNSCC), 951 days for Esophageal Cancer (EC), 660 days for Ovarian Carcinoma (OC), 738 days for Biliary Tract Adeno Cancer (BTAC), 597 days for Colorectal Carcinoma (CRC), 735 days for Cervical Cancer (CC) and 1085 days for Pros- tate Cancer (PC). Conclusion: Stability of PD-L1 IHC 22C3 pharmDx stained slides is of interest when patient specimens are re-scored for a different cutoff or for research purposes. These studies demonstrated a minimum stained slide stability of 550 days across the 10 tumour types studied, provid- ing high confidence in the assay performance on aged, stained slides when stored in the dark at ambient temperature. The stability of slides stained with PD-L1 IHC 22C3 pharmDx remains a parameter specific to tumour type. PS-07-006 A way to teach pathology through gamification: Clue and Escape 60 S. Maria Macêdo, R. Barreira Pitombeira, L. Barreira Pitombeira, G. Machado Nepomuceno Correia Lima, C. Albuquerque Colares, C.C. Rodrigues Augusto Gonçalves, I. Castelo Branco Fontenele Costa, V. Veras Pereira de Matos Filho, A.D. Muniz de Sousa, V. Vieira Freitas Araujo, J. Carneiro Melo, E. Tome de Sousa, D. Nunes Oliveira* *University of Fortaleza, Brazil Background & objectives: Gamification is a game thinking-based strategy, proven by studies to enhance learning in academic contexts, by increasing apprenticeship efficiency and engagement. This paper aims to report the experience with gamification as a teaching tool in pathology.Gamification is a game thinking-based strategy, proven by studies to enhance learning in academic contexts, by increasing apprenticeship efficiency and engagement. This paper aims to report the experience with gamification as a teaching tool in pathology. Methods: Two games were created as tools for teaching pathology in the sixth semester of the medical course at a private university. One of the games was about chronic obstructive pulmonary disease and incorporated elements from the "Clue" game, while the second one, addressed Hodgkin’s and non-Hodgkin’s lymphoma, based on the game “escape 60”. Results: Regarding the clue game, 48 responses were received, with 97.9% (47) stating that the game aided in knowledge fixation and met learning objectives. Ratings were as follows: 58.3% gave it a 10, 25% gave a 9, 4.1% gave an 8, 4.1% gave a 7, and 2.08% gave a 5, averaging 9.3. Additionally, 95.8% want the game to continue being applied. For "Escape 60," 23 responses were received, with a consensus that this strategy aided in knowledge fixation, met learning objectives and should continue being used. Ratings were: 65.2% gave a 10, 30.4% gave a 9, and 4.3% gave an 8. Regarding the clue game, 48 responses were received, with 97.9% (47) stating that the game aided in knowledge fixation and met learning objectives. Ratings were as follows: 58.3% gave it a 10, 25% gave a 9, 4.1% gave an 8, 4.1% gave a 7, and 2.08% gave a 5, averaging 9.3. Additionally, 95.8% want the game to continue being applied. For "Escape 60," 23 responses were received, with a consensus that this strategy aided in knowledge fixation, met learning objectives and should continue being used. Ratings were: 65.2% gave a 10, 30.4% gave a 9, and 4.3% gave an 8. Conclusion: This study demonstrated that the use of gamification resulted in positive results, supporting the validity of this innovative approach in the teaching-learning process. Furthermore, this study highlighted scholarly perspectives on creating and utilizing dynamic resources aimed at increasing student engagement. PS-07-007 Effects of ischemia and fixation time on specimens stained with PD-L1 IHC 22C3 pharmDx (Code SK006) C. Roach*, J. Musser, S. Tabuena-Frolli, S. Hund, K. Kulangara *Agilent Technologies, USA Background & objectives: PD-L1 IHC 22C3 pharmDx is a qualitative immunohistochemical (IHC) assay for PD-L1 expression in FFPE speci- mens routinely processed for diagnostic evaluation. A pre-analytical variable study has been performed to assess the effects of ischemia and fixation time on PD-L1 expression. Methods: Normal human placenta tissue was used as a model since syn- cytiotrophoblastic cells have features similar to malignant cells. Fresh tissue was procured, prepared and then subjected to ischemic times of 0- 24 hours. Specimens were then fixed in 10% NBF for 6 - 72 hours. A cohort of 216 placenta blocks were stained by IHC using PD-L1 IHC 22C3 pharmDx. Results: Stained slides were evaluated and assessed for any changes in PD-L1 expression and overall staining intensity by comparing speci- mens prepared with various ischemic and fixation times. This data demonstrated average IHC intensity of PD-L1 expression differences of ≤ 0.5 grade between sections processed with ischemic times 0-24h and fixation times 6-72h. To leverage these results for neoplastic speci- mens, a titration study was performed to compare PD-L1 expression on placenta and non-small cell lung cancer (NSCLC) to assess similarities in sensitivity. Similar sensitivity to titrations was observed between placenta and NSCLC.