ECP 2022 Abstract Book

Virchows Archiv (2022) 481 (Suppl 1):S1–S364 13 Conclusion: In conclusion, our data supports that pathologist- performed FNAC is an important part of the initial evaluation in patients presenting with a head and neck mass, and helps in avoiding unnecessary surgical procedures with high diagnostic accuracy. During the FNAC session, the pathologist examines the patient, takes a good clinical history, performs the aspira- tion procedure, prepares the slides with rapid on-site assess- ment, checks the adequacy, and then continues the process until sufficient material is obtained to ultimately make a diagnosis. PS-11-016 Evaluation of a cytomorphology-molecular co-test of urine in bladder cancer patients E. Thodou, C. Apostolopoulou, V. Tzortzis, L. Mitrakas, M. Stra- taki*, R. Papamichali, K. Zacharouli, E. Panteliadou, M. Ioannou, M. Samara *Department of Pathology, Faculty of Medicine, School of Health Sciences, University of Thessaly, Greece Background & objectives: Urine cytology used for monitoring of Non-Muscle Invasive Bladder Cancer (NMIBC) has low sensitivity for low-grade tumours, which present FGFR3 mutations. These activat- ing mutations were examined in urine processed with THIN PREP, as potential biomarker to improve cytology performance. Methods: We examined 38 urine specimens in THIN PREP. Α slide for cytology was prepared and the remaining sample was used for DNA isolation. Exons 7 and 10 of FGFR3 gene harbouring hot spot mutations were amplified by PCR and analysed by direct sequenc- ing. Molecular results were compared with cytology reported according to Paris system and were correlated to histology. Results: Cytology was performed in urine samples of 38 patients; 26 cases were classified as high-grade urothelial carcinoma (HGUC), 6 as atypical urothelial cells (AUC) and 6 as suspicious for high-grade urothelial carcinoma (SHGUC). Sequence analysis of both exons 7, 10 of the FGFR3 gene was performed. Exon 10 analy- sis revealed no mutations. However, 4 patients had a c.746C>G substitution leading to p.S249C mutation at exon 7 of FGFR3 gene. Cytology report was AUC in two of them and SHGUC in the remaining two. The corresponding histology showed low- and high- grade carcinomas in three and one cases, respectively. None of the patients classified as HGUC had FGFR3 mutations. Conclusion: Urine cytology is useful for detecting HGUC, whereas AUC does not provide specific information and may include low- grade tumours. We found that FGFR3 activating mutation p.S249C in exon 7 is present mostly in low-grade carcinomas and excep- tionally in high-grade carcinomas. This preliminary study shows that a cytomorphology-molecular co-test in the same urine sample could contribute to define the atypical and suspicious categories of cytology by depicting low-grade tumours. Thus, a more precise stratification of patients can be achieved. PS-11-017 Cytological rapid on-site evaluation in pulmonary biopsies: optimizing material and accelerating diagnosis C. Perelló i Fabregat*, F. Andreo García, E. Calvo Serrano, J. Pagès Barón, A. Castillo Gandía, J. García-Gómez, P. Serra Mitjà, A.J. Solis Solis, M. Ávila Terzi *Hospital Universitari Germans Trias i Pujol, Spain Background & objectives: The in situ cytological assessment of pul- monary biopsies obtained by different techniques allows evaluating the quality and quantity of the material obtained, avoiding reintervention especially in hard-to-reach lesions and speeding up the definitive diagnosis. Methods: We present a prospective study of 23 cases comparing the in situ assessment of the imprint of the biopsy with the final delayed diagnosis. The rapid on site evaluation (ROSE) technique was performed by fixing the imprint in alcohol and staining for 1 minute with haematoxylin. A cytotechnician and a cytologist evaluated the sample (65% of them through telecytopathology). Results: Cases were classified as positive, negative, insufficient, suspicious of neoplasia and undetermined. A concordance of 82.6% was reached between both methods (19/23 cases). There was only one case with disagreement between ROSE and the definitive diagnosis: the former classified as negative and the latter positive (squamous cell carcinoma). ROSE was not conclusive in 13% cases (3/23): one of them suspicious for carcinoma with a final diagnosis of infiltrating adenocarcinoma, a second one undetermined with a diagnosis of metastatic adenocarcinoma and the last one with insufficient material in the imprint to reach a proper orientation that resulted in a negative diagnosis for neoplasia. Conclusion: Carrying out an in situ cytological assessment of lung biopsies is a practical approach that is usually concordant with the definitive diagnosis and could facilitate and optimize the obtention of an adequate sample to avoid extra intervention by evaluating the adequacy of the sample. Thus, an adequate and representative sample of the lesion facilitates a more accurate morphological, immunohistochemical and molecular study, leading to an important impact in prognosis and targeted treatment of patients in the era of personalized medicine. PS-11-018 Clinical trial: a new method for preparing cell blocks from paucicellular aspirates O. POP*, C.A. Sanda, A.E. Stefan, D. Gologan, S. Musat, M.O. Leavitt, A. Jakob *University of Oradea, Romania Background & objectives: Multiple methods have been historically utilized for obtaining cell blocks with significant variation and lack of reproducibility. Complex, time-consuming steps generate high losses of cellular material whilst the low yield of sections precludes evaluating coordinate immunoreactivity patterns on serial sections. Methods: The CytoPod™ method for cell blocks employs a con- cave nitrocellulose filter affixed to a perforated sectionable matrix and vacuum filtration for capturing cellular material. Clinical sam- ples such as: EBUS-TBNA, BAL, bronchial and pleural aspirates and ascites fluid were processed in duplicate into cell blocks using both the Thermo Scientific Shandon Cytoblock and the CytoPod™ systems. Results: After the preliminary steps of washing/concentrating the aspirates (if needed) both methods allowed the preparation of cell blocks. Remarkably, the CytoPod™ method performed with low- to substantially zero-cell losses, was compatible with all usual fixa- tives and from each paraffin block over 150 serial sections were obtained. Even with very low volume samples (<1 mL) and cel- lularity (<100,000 cells) the diagnostic material was distributed uniformly on both the bottom and along sidewalls of the filter. Serial sectioning was undemanding while reading the slides proved expeditious due to predictable cellularity and layout of the diag- nostic material within the sectionable matrix. No interference with IHC and ISH was observed. Conclusion: Cell blocks from paucicellular aspirates are a cost- effective option in cytopathology and can be comparable in diag- nostic value to FFPE from biopsy. Such a practice in a universal fashion would result in reproducible results with interinstitutional S126