ECP 2023 Abstracts

S219 Virchows Archiv (2023) 483 (Suppl 1):S1–S391 13 changes, significant inflammatory infiltrate and occlusion of some vessels by black, opaque inframillimetric microspheres (Y-90). Conclusion: While effective, TACE can result in serious complica- tions, including "post-embolization syndrome”, hepatic abscess, acute liver failure, and acute kidney injury. NAP is an uncommon but seri- ous complication. SIRT is generally well tolerated, but patients may experience gastrointestinal adverse events resulting from migration or misallocation of Y-90 microspheres. Healthcare providers must monitor patients for adverse effects and be aware of potential risks. Further studies are needed to better understand these issues, including the association of different beads with adverse effects. E-PS-07-005 Cholestatic HCV-related cryoglobulinemia, a new clinical and pathological entity: a case-control study S. Ammendola*, A. Dalbeni, S. Romeo, F. Cattazzo, A. Tomezzoli, D. Sacerdoti *Department of Diagnostics and Public Health, Section of Pathology, University of Verona, Italy Background & objectives: This study aims to explore the correla- tion between the presence of mixed cryoglobulinaemia (MC) and plasma cells content and distribution on liver histology and its role in the development of cholestasis in patients with non-eradicated HCV-related chronic hepatitis (CHC). Methods: CHC patients were identified through clinical records. Cholestatic parameters, HCV-RNA serum levels, HCV genotype, plasma MC levels were retrieved; plasma cells presence and distri- bution were assessed on Hematoxylin&Eosin stained slides and by immunohistochemistry using anti-CD38 antibody. Patients with a history of autoimmune diseases were excluded. The Mann-Whitney U or the Chi-squared tests and stepwise multivariate analysis were performed. Results: Sixty-two participants (57.3 ± 11.1 years; males = 50%) with CHC were enrolled: 31 non-eradicated HCV+/MC+ patients matched for age, sex and HCV genotype with 31 HCV-/MC- patients. Serum cholestasis was significantly higher in MC + group (p = 0.02) and correlated in univariate analysis with cryoglobulinemia (OR 6.9; p = 0.02). At histological assessment, the number of plasma cells in one hotspot at 40X magnification was significantly higher in the MC + group (p=0.01) and these were more commonly found in aggregates compared to the MC- group (p=0.05). At multivariate analysis with genotype, HCV-RNA, steatosis, gender and age, cholestasis was only correlated to MC + (p = 0.01). Conclusion: Our study identified for the first time a correlation between MC, cholestasis and an increased number of intrahepatic plasma cells in patients with non-eradicated CHC. These findings have important clinical implications since MC is the most com- mon extrahepatic manifestation in CHC, sometimes persisting after virus eradication. Future studies are needed to understand how MC causes cholestasis and if the increase in plasma cells content can help predict the severity of liver disease after virus eradication in MC+ patients. E-PS-07-006 Multiseptate gallbladder: case series of 6 patients and the litera- ture review H. Berber*, E. Ozgur, H.K. Kahraman, S. Yüksel, S. Kiremitci, B. Savaş *Ankara University Medical School, Pathology Department, Turkey Background & objectives: The multiseptate gallbladder (MSG) is a rare anomaly of gallbladder. So far, fifty-nine cases have been reported in literature since 1963. Herein, we share the clinical, radiological and histomorphological features of 6 cases in our archives. Methods: Six cases of MSG were diagnosed in our clinic between 2005-2023. Symptoms, laboratory data and radiological examina- tion of these cases were obtained from the hospital records. All his- tological preparations of the cases were reevaluated according to their presence of muscle fibres in septa, inflammation and additional findings. Also we conducted a literature review using the PubMed database. Results: Among all cases, mean age was 11,91 (range:6 months-37 years). Two of them were male, 4 were female. Only one case (5 year- old male) complained of abdominal pain, while others were asympto- matic. Calculus was not detected in any of them. A 6-month-old girl had been under investigation for biliary atresia since antenatal period. Mild elevation of liver function tests was detected in this case. Septal muscle fibres were detected in most of them (n=5) as in the literature (88,9%). Mild chronic inflammation was observed in all. In the litera- ture, mean age was 27,34 (range:15 days-70 years), most of them were adult (n=39, 66,1%), female (n=40, 67,8%) and symptomatic (n=40, 67,8%). Conclusion: MSG is a rare biliary anomaly that can occur in chil- dren and adults. Although majority of the patients in literature present with biliary symptoms, they may be asymptomatic like most of our cases. Although malignancy hasn’t been reported in MSG yet, it’s been indicated that the risk of malignant transformation may increase in some associated anomalies. Most of the publications until now have been about radiological imaging, but less about histomorphological features. Further information is needed to understand this anomaly. E-PS-07-007 Prognostic value of dihydropyrmidine dehydrogenase (DPD) expression in lymph node metastases in pancreatic ductal adeno- carcinoma (PDAC) H. Blomstrand*, F. Groth, M. Bodarve, N. Elander *Department of Pathology, Linköping University Hospital, Department of Biomedical and Clinical Sciences, Linköping University, Sweden Background & objectives: Previous reports have linked intratumoral expression of dihydropyrmidine dehydrogenase (DPD) with survival in resected PDAC treated with adjuvant chemotherapy. This study investi- gated this relationship in primary tumours and lymph node metastases (LN) from a population-based cohort of Swedish patients. Methods: A TMA including primary tumours and lymph node metas- tases of 275 resected PDAC-specimens was constructed. DPD was analysed with immunohistochemistry (Abcam anti-DPD antibody, ab134922) and staining intensity scored by two observers (HB,NE). Samples were categorised into DPD-low (score 0-1) and DPD-high (score 2-3). The prognostic value of DPD and other clinicopathologi- cal parameters were analysed with univariable and multivariable Cox regression. Results: DPD scoring was successful in 262 cases. 120 received gemcitabine and 40 other types of adjuvant chemotherapy. Between observer concordance was excellent (Kappa=0.81). In 23% the LN- score deviated from the primary tumour score (15% low-to-high, 8% high-to-low). Univariate cox regression analyses revealed impaired OS in the DPD-high group for mean (OS 15.9 vs 22.5 months, HR 1.52, p=0.008) and LN-only scores (OS 14.0 vs 19.2 months, HR 1.42, p=0.066). DPD-high patients had shorter relapse-free survival (RFS 10.8 vs 12.9 months, p=0.036). LN-DPD-high was linked with shorter OS among gemcitabine treated patients (p=0.039). In multivariable analyses, LN-score (HR 1.52, p=0.044), beside TNM- stage, LVI, and adjuvant treatment remained independent factors for OS.