ECP 2022 Abstract Book

Virchows Archiv (2022) 481 (Suppl 1):S1–S364 13 Methods: A retrospective review of 417 consecutive patients from 2014-2021 identified 65 patients with ASCUS cytology and high- risk HPV strains (other than 16 and 18). Progression from ASCUS to low grade squamous intraepithelial lesion (LSIL), atypical squamous cell cannot rule out high grade (ASC-H), high grade intraepithelial lesion (HSIL) or cancer in cytology was assessed and stratified by HPV vaccination status. Results: A total of 65 female patients (age range = 22-71 years, mean age = 37.2 years) who were infected with high-risk HPV strains (other than 16 and 18) and had ASCUS cytology were included. In a follow up period ranging from 6 months to 5 years, 50 out of the 65 patients had no progression, 12 progressed to LSIL, 1 had ASC-H and 2 had HSIL on Papanicolaou smears. 17 patients received bivalent, trivalent or quadrivalent HPV vaccines whereas only 4 patients received the nonavalent HPV vaccine. The rate of progression was 25% in unvaccinated patients, 19% in vac- cinated patients and 0% amongst patients who were administered the nonavalent vaccine. Conclusion: Our preliminary findings indicate a high associa- tion of high-risk HPV strains other than 16 and 18 and progres- sion from ASCUS to worse abnormal cervicovaginal cytology, especially in the patients who did not receive the nonavalent vac- cine. Of note, ASC-H and HSIL progression was observed only in unvaccinated patients. We will explore these associations in larger population datasets to confirm our findings and potentially encourage utilization of the more comprehensive nonavalent HPV vaccine. PS-11-010 Atypical urothelial cells: two-year-experience with the Paris system for reporting urinary cytology in tertiary care centre pathology I. Kholová*, E. Pöyry, V. Nykänen, E. Viljanen, J. Pulkkinen, M. Laurila *Fimlab Laboratories, Finland Background & objectives: The implementation of The Paris System for Reporting Urinary Cytology (TPS) emphasizes detection of high- grade urothelial carcinomas in urine. “Atypical urothelial cells” is a TPS category reserved for cytological samples with mildly or moder- ately atypical urothelial cells. Methods: Urinary cytological specimens from the first two- year-period (January 2017-December 2018) after TPS introduc- tion were retrospectively analysed with cyto-histological cor- relations. The timeframe for histological follow up was at least 6 months. Results: Total of 3741 urinary specimens were analysed during the study period with the following categorization: 49 (1.31%) insufficient samples, 3334 (89.12%) negative samples, 205 (5.48%) “atypical urothelial cells” samples, 89 (2.38%) “suspicious for high-grade urothelial carcinoma” samples, 62 (1.66%) cytological “high-grade urothelial carcinoma” samples and only two (0.05%) “low-grade urothelial neoplasm” samples. Out of 205 “atypical urothelial cells” samples, histological follow up was available in 97 (47.32%) cases: 27 (27.84%) were low-grade urothelial carcinomas, 34 (35.05%) high-grade urothelial carcinomas and 36 (37.11%) non-tumorous lesions in final histology. Conclusion: The risk of malignancy was 29.8% in all “atypical urothelial cells” samples and 62.9% in histologically verified speci- mens. Urinary cytology is a rapid, non-invasive and cost-effective method both in diagnosing and follow up of urothelial malignancies with TPS increasing its clinical value. Funding: VTR grant from Pirkanmaa Hospital District PS-11-011 Fine needle aspiration biopsy of pilomatrixoma (Cytological features of 6 cases histologically approved) B. Guzelbey, S. Erdogan-Durmus* *Department of Pathology, Prof. Dr. Cemil Tascioglu City Hospi- tal, Istanbul, Turkey Background & objectives: Pilomatrixoma is a rare, benign skin adnexal tumour of hair matrix, commonly presents as a slow growing firm to hard intradermal or subcutaneous solitary nodule. We present our experience with fine-needle aspiration biopsy (FNAB) of 6 histo- logically confirmed pilomatrixoma cases. Methods: Our series includes FNAB slides of 6 cases of pilo- matrixoma, which were histologically approved. The slides were prepared by conventional method and liquid-based cytology tech- niques. Conventional method was used to prepare the cell blocks. Results: The ages of patients ranged from 8-63 years old. The male-to-female ratio was 2/1. All cases occurred in the head and neck area. The aspirates were cellular. The smears contained mod- erate to high numbers of basaloid cells, anucleated squamous cells and debris. Basaloid cells were small and uniform. They were arranged in crowded groups. The chromatin was finely granular and consistently even in distribution. Most of the smears were rich in giant cells and cell debris in the background. Mitotic figures and sheets of ghost cells were identified as well. Five cases were diagnosed as pilomatrixoma and one as epidermoid/dermoid cyst. Conclusion: Excisional biopsy is often the preferred method of diagnosis for the cutaneous masses. There are very few reports on the cytologic features of pilomatrixoma in FNAB smears. The combination of basaloid cells, ghost cells, squamous and giant cells are the key features that will allow a conclusive diagnosis of pilo- matrixoma by FNAB. PS-11-012 Metastases of extrapulmonary malignancies in mediastinal lymph nodes sampled by Endobronchial ultrasound-guided transbronchial needle aspiration S. Erdogan-Durmus*, A.B. Goktas, Z.B. Erdem *Department of Pathology, Prof. Dr. Cemil Tascioglu City Hospi- tal, Istanbul, Turkey Background & objectives: Endobronchial ultrasound-guided trans- bronchial needle aspiration (EBUS-TBNA) is also useful method for detecting metastases of extrapulmonary malignancies (EPM) as well as metastases of lung cancer. We aimed to analyse the cytomorphological and immunohistochemical features of EPM metastases in mediastinal lymph nodes. Methods: The 375 EBUS-TBNA samples were analysed retrospec- tively that reported by a cytopathologist in an 18-month period. Demographic data and clinical information were obtained from pathology reports. The slides were prepared by conventional method and liquid-based cytology techniques. Conventional method was used to prepare the cell blocks. Results: Of the 375 EBUS-TBNAs, 147 (39.2%) were mediastinal LN metastases from lung cancer, 10 (2.7%) were metastases from EPM, two (0.5%) were lymphoma, and 199 (53.1%) were benign. The mean age metastasis of EPM was 67.2 (range: 52-86) with a male-to-female ratio 3:2. The distribution of metastases from EPM as follows: adenocar- cinoma of gastrointestinal tract: 3, breast carcinoma: 2, prostatic adenocarcinoma: 2, renal cell carcinoma: 2, and papillary thyroid carcinoma: 1. Immunohistochemical study was performed in 9 of 10 cases. Cell block was not formed in one case. Most used immu- nohistochemical marker was TTF-1 (n:9). S124