ECP 2022 Abstract Book

Virchows Archiv (2022) 481 (Suppl 1):S1–S364 13 PS-15-009 Analysis of p62 immunoexpression in metastatic samples of lung adenocarcinomas to the brain revealed a group of patients with a poorer prognosis I. Fernandez-Vega*, D. Corte-Torres, A. Vallina, J.C. Celis Pinto, M. Rubiera, S. Fernández Menéndez, K.M. Piña Batista *Hospital Universitario Central de Asturias; Universidad de Oviedo, Faculty of Medicine, Spain Background & objectives: p62 is a multifunctional adaptor protein implicated in the crossroads of autophagy, apoptosis, and cancer. Our aim was to study the immunoexpression of p62 in samples from lung adenocarcinoma and their respective brain metastases and its possible clinical relevance. Methods: Twenty-six consecutive patients with lung adenocarci- noma and subsequent brain metastasis surgically removed between 2007 and 2019 were studied. Tissue arrays were produced using a 2 mm diameter needle. Immunohistochemical studies were conducted and analysed by the H-Score method. Statistical analysis of these findings was carried out using the SPSSv25; p<0.05 program. Results: Positive immunoexpression for p62 was detected in more than 80% of both primary tumours and their brain metastasis with significant differences (112,38 ± 101,28 vs 85,71 ± 88,97; p= 0,035). More than 60 points of p62 immunoexpression in metastatic brain samples of lung adenocarcinoma showed a group of patients with a significant lower overall survival (56,61 ± 15,21 vs 111,03 ± 11,21 weeks; p= 0,039) and disease-free survival (4,55 ± 1,91 vs 82,47 ± 20,10 weeks; p= 0,005). Conclusion: Significant overexpression of p62 was noted in pri- mary lung adenocarcinomas compared to the metastatic tissue in the brain. More than 60 points of p62 immunoexpression in meta- static brain samples of lung adenocarcinoma revealed a group of patients with a poorer prognosis. Funding: A competitive grant to IFV in the intramural call for the promotion of research projects of the Institute of Health Research of the Principality of Asturias, ISPA (2020-2022) PS-15-010 NGS-based molecular profiling and liquid biopsies: an assess- ment of pathologists and oncologists knowledge and attitudes N. Dorkhom*, D. Middleton, T. Abair, A. Vingiani, G. Pruneri *Medscape Oncology, The Netherlands Background & objectives: This activity investigated the knowledge gaps of haematologists/oncologists (hem/oncs) and pathologists regard- ing the use of next generation sequencing (NGS)-based molecular pro- filing and liquid biopsies in clinical practice. Methods: A CME-certified clinical practice assessment compris- ing 30 multiple-choice questions that measured knowledge, atti- tudes, and perspectives regarding NGS-based molecular profil- ing and liquid biopsies was developed. The self-assessment was available online to physicians without monetary compensation. Respondent confidentiality was maintained, and responses were deidentified and aggregated prior to analysis. The activity launched June 8, 2021; data through December 1, 2021, are presented. Results: The number of hem/oncs and pathologists answering each of these 30 questions ranged from 58 to 340. Only 54% of hem/ oncs and 52% of pathologists knew that the turnaround time of NGS analysis of liquid biopsies is approximately 50% shorter com- pared to NGS analysis of tissue biopsies. Furthermore, only 44% of hem/oncs and pathologists were aware that real world data in NSCLC showed that patients receiving matched targeted therapy after genomic profiling of tissue biopsy versus ctDNA had similar PFS and ORR. The percentage of hem/oncs who answered each of the 20 knowledge questions correctly ranged from 17% to 83% while the range for pathologists varied from 16% to 89%. Conclusion: NGS-based molecular profiling and liquid biopsies are becoming increasingly important in informing treatment deci- sions for patients with cancer. However, only 26% of hem/oncs and 35% of pathologists are confident in explaining to their colleagues how to apply NGS in clinical practice, and only 27% of hem/oncs and 28% of pathologists are confident in their ability to use liquid biopsies in clinical practice. This demonstrates the importance of further educating clinicians on these topics. Funding: This activity was supported by an independent educa- tional grant from Thermo Fisher Scientific PS-15-011 Study of gene expression by in situ hybridization in tissues with prostate adenocarcinoma routinely processed I. Benedetti*, L. Barrios *Universidad de Cartagena, Colombia Background & objectives: The chromogenic in-situ hybridization (CISH) RNAscope® amplifies specific mRNA signals without back- ground noise, and detects individual molecules as points feasible to be quantified. It allows high resolution in the study of the expression of each cell within its morphological context. Methods: The in situ gene expression was evaluated by CISH in routinely processed prostate tissue. CISH assays were performed under standard conditions of the RNAscope® 2.5HDBrown ISH protocol, in a tissue microarray. Considering a positive stain eas- ily visible under the microscope, nuclear and cytoplasmic dotted staining and signal strength for mRNA of each gene in the tissue cores were measured. Results: Expression of the endogenous gene Hs-PPIB (Peptidyl- prolyl-Isomerase-B) as a positive control, the bacterial gene dapB (dihydrodipicolinate-reductase) as a negative control for the back- ground signal, and the target gene CXXC5, were evaluated in a prostate tissue microarray constructed from prostatectomy samples of patients with localized prostate cancer, including 381 cores of benign prostate tissue and prostate adenocarcinoma. The quality of the mRNA was variable along the tissue cores of the microarray, most showed moderate to strong staining of the positive control with little background staining. There was a correlation between mRNA expression of the constitutive endogenous gene Hs-PPIB and the target gene CXXC5. Conclusion: CISH makes it possible to detect isolated mRNA molecules in routinely processed tissues, study cell gene expres- sion in context without destroying tissue morphology, compare it between heterogeneous cell populations, and locate molecu- lar markers within the tumour microenvironment. Analysing the expression of mRNA in prostate cancer (PCa) tissues routinely processed by CISH would allow risk stratification and prognostic markers. Funding: Universidad de Cartagena, Cartagena, Colombia. PS-15-012 Arylsulfatase B gene expression profile in colorectal cancer Z. Kovacs*, I. Jung, R.I. Stefan-Van Staden, A. Patrichi, S. Gurzu *George Emil Palade University of Medicine, Pharmacy, Science, and Technology of Targu Mures, Department of Biochemistry and Environmental Chemistry, and Research Center of Oncopathology and Transdisciplinary Research (CCOMT), Romania S143