ECP 2022 Abstract Book

Virchows Archiv (2022) 481 (Suppl 1):S1–S364 13 biopsy stage, tumour type, immunohistochemistry studies, TERT promoter status and percentage of SC. From the clinical history, we obtained data of appearance and location at cystoscopy and survival. Results: We identified 20 patients with a mean age of 79 years, 17 of them were diagnosed at transurethral resection (TUR). In cystoscopy 6 were located in the left lateral wall and 16 had a solid aspect. Thirteen patients had stage T2 in TUR. Cytokera- tin was positive in all 20 cases. All the tumours that underwent TERT promoter were mutated (5 cases). Seven patients underwent cystectomy. Fourteen patients had mixed high-grade UC and SC (mean 63% of the tumour) and 6 patients had the entire sample with SC. Twelve patients died with a mean survival of 17 months. Five patients had previous radiotherapy with a mean of 13 years before diagnosis. Conclusion: Sarcomatoid carcinoma of the bladder presents at an advanced age and has poor prognosis due to low survival. In our series, 70% SC had conventional urothelial carcinoma with sarcomatoid component, 65% were at least T2 at diag- nosis. Cytokeratin was positive in all of our cases, and TERT promoter was mutated in the 5 cases studied. Of our patients, 25% had previous radiotherapy and 75% died because of the disease. Our findings are similar to those previously described in the literature. PS-26-048 Gleason score before and after radical prostatectomy: a com- parative study V. Trivunović*, T. Lakic, M. Šunjević, N. Stanulović, M. Panjković *Center for Pathology and Histology, University Clinical Center of Vojvodina, Novi Sad, Serbia Background & objectives: The Gleason score (GS) places patients with prostate cancer in one of five categories (ISUP Grade Group). GS being the most important prognosis predictor, we investigated reli- ability and factors influencing a core needle biopsy (CNB) in predicting operative sample GS. Methods: Retrospective study was conducted at the Center for Pathology and Histology of the University Clinical Center of Vojvodina. Querying patients’ histories we identified 56 men who underwent CNB and radical prostatectomy (RP) at our institution in a two-year period (2018-2019). Preoperative and postoperative parameters were collected. Correlation and influence among the parameters were statistically analysed. Results: Patients’ average age was 66.75±4.24 years. The most com- mon tumour was GS 3+4 (ISUP GG 2) - 37.5%, pT2 stage (60%). GS was upgraded on RP material in 50% of patients. All patients with CNB GS 3+3 (25%) had a higher GS on RP material. For 18 patients (32%) the score remained unchanged, while 10 patients (17.8%) had a lower GS postoperatively. Linear regression showed that with every year of the patients’ age, GS and the number of positive biopsy samples increased (b=0.05, p=0.03; b=0.025, p=0.005 respectively). Spear- man’s test showed low statistically significant correlation between CNB GS and RP GS (r=0,2900). Conclusion: Accurate defining of GS is of utmost significance for appropriate treatment of prostate cancer especially in elderly patients whose GS and number of positive biopsies tend to be higher. CNB is a modestly reliable method for defining GS/ISUP GG of prostate cancer, considering high number of upgraded GS on postoperative material. Therefore, postoperative assessment of RP specimen is mandatory for confirming GS defined on CNB and possible adjustment of treatment method. PS-26-049 The impact of pathology review in a population-based cohort of 770 clinical stage I testicular germ cell cancer patients T. Wagner*, B. Grønkær Toft, J. Lauritsen, M. Bandak, G. Dau- gaard, D. Berney *Department of Oncology, Copenhagen University Hospital, Rig- shospitalet, Copenhagen, Denmark Background & objectives: Inaccurate pathology reporting may con- tribute to the ambiguous results on histopathological features as pre- dictors of relapse in patients with clinical stage I testicular germ cell cancer (TGCC). This study compares the primary pathology reports with those obtained by pathology review. Methods: We reviewed all histopathological slides from 770 patients who were diagnosed with stage 1 TGCC in Denmark between 2013 and 2018. We assessed tumour type, pathologic tumour (pT) stage according to the 8th edition of the AJCC TNM staging system, lymphovascular invasion (LVI) and invasion of stromal rete testis (RTI), hilar soft tissue (STI), epididymis, sper- matic cord and tunica vaginalis. Results: Following the pathology review, the tumour type was revised in 1% of the cases, including two spermatocytic tumours initially misclassified as pure seminomas. Overall, reporting of RTI was revised in 20% of the cases; of those initially called absent 24% were changed to present, and of those initially called present 11% were changed to absent. The reporting of LVI was revised in 16% of the cases. There was a discrepancy rate of 13% regarding the reporting of STI. The pathologic stage was revised in 23% of cases, mostly owing to the revised variables of LVI and STI in these cases. Epididymis status was revised in 3% of the cases. Conclusion: Inaccurate histopathological interpretation of TGCC specimens is not uncommon and may lead to incorrect tumour classification and pathological staging. This study highlights significant reporting variability on histopathological features in testicular tumours. Therefore, the decision to give adjuvant therapy in clinical stage I TGCC patients based on the findings of decentralized pathologic assessment is problematic. Centralized pathology review is deemed necessary if the true prognostic value of histopathological features is to be determined. Funding: The Danish Cancer Society PS-26-050 Prostatic calculi supress the expression of VEGF in the prostate cancer A. Piddubnyi*, R. Moskalenko *Sumy State University, Dept. of Pathology, Sumy, Ukraine Background & objectives: Prostatic calculi (PCa) are associated with the development of prostate cancer (PC) bone metastases. Nevertheless, their effect on angiogenesis remains unclear. Objective:To study the effect of prostate calculi on the expression of Vascular Endothelial Growth Factor (VEGF). Methods: For this study, we used 60 PC samples (30 PC samples with PCa and 30 samples without biomineralization). Initially, all samples were stained with hematoxylin-eosin. Immunohistochem- istry was performed with antibodies against VEGF. Data sets were analysed by the Shapiro-Wilk test and Mann-Whitney’s U-test. Results: The presence of PCa in cancer tissue was associated with tissue damage, oedema, epithelium desquamation, inflammation and foci of necrosis. We detected significantly (p < 0.05) lower expression of VEGF by PC tissue with biomineralization. This provided evidences that PCa do not cause the intensification of S181