ECP 2023 Abstracts

S211 Virchows Archiv (2023) 483 (Suppl 1):S1–S391 13 Background & objectives: Eosinophilic oesophagitis (EoE) is immune-mediated disease with increasing incidence, becoming the second most common inflammatory condition of oesophagus after gastro-oesophageal reflux disease. The aim of the study was to deline- ate histopathological features to distinguish between EoE and reflux oesophagitis (RE). Methods: Biopsy was performed in 17 patients that fulfilled EREFS criteria for EoE (80 biopsies: 52 distal and 28 proximal) and in 10 patients with RE (41 biopsies: 30 distal and 11 proximal). Biopsy specimens were fixed in 10%-neutral buffered formalin and stained with haematoxylin and eosin and combined PASD/Alcian Blue. EoE histology scoring system (EoEHSS) was applied for histological evaluation. Results: Male predominance was observed in both groups (11/17 and 7/10, respectively), but patients with EoE were younger [Me 32,8 (21-41) vs 52,5 (43-66) years]. EoEHSS activity (12 vs 7) and stage scores (12 vs 6,5) for EoE were almost twice as high as for RE. Peak eosinophil count reached 220 per high power view x400 for EoE [Me 65 (36-116,5)] and 12 for RE [Me 3 (3-7)]. Higher severity of intercel- lular space dilatation and basal cell hyperplasia favoured EoE: for both median scores were 3 compared to 1 for RE. Eosinophilic abscesses and surface layering were noticed exclusively in EoE and comprised for 58,8% and 17,6% of cases respectively. Conclusion: Predominantly eosinophilic intraepithelial infiltration of the oesophagus is a hallmark for EoE, though various number of intraepithelial eosinophils may be revealed in other conditions includ- ing RE. For the aim of our research only RE cases with any eosino- phils in oesophageal mucosa were selected. EoEHSS appeared to be a reliable tool to distinguish EoE from RE. The density of intraepi- thelial eosinophils, eosinophilic abscesses and surface layering were the most useful histological features for differential diagnosis between EoE and RE. E-PS-06-073 Microinvasive ductal carcinoma arising from anogenital mam- mary-like glands, a case report D. Piñol Ballús*, A. Prat, C. Fumagalli, V. Fusté Chimisana, M.P. Hernandez, J. Szafranska *Hospital de la Santa Creu i Sant Pau, Barcelona, Spain Background & objectives: Background: Anogenital mammary-like glands (AGMLG) are an ectopic breast tissue found in the anogenital region of both males and females and can give rise to lesions identical to their counterparts in the native breast. Methods: Case summary: We present a case of a 64-year-old woman, without relevant personal history, with a painless perianal mass. The endoscopy revealed a 14 mm non-encapsulated solid dermal lesion with a minor cystic component. Patient underwent surgical resection. Routine study with H&E and immunostains were performed. Results: Discussion: Histologic examination showed the presence of anogenital mammary-like glands (AGMLG) and a malignant component resembling an “in situ” ductal carcinoma. The neoplasm displayed a solid and papillary growth pattern with foci of stromal invasion and presence of extramammary Paget disease (EMPD). Both the benign and neoplastic components were positive for CK7, CK19, GCDFP-15, oestrogen and androgen receptors and partially positive for progesterone receptors, while CK20 and CDX2 stains were nega- tive. Myoepithelial cells (p63 positive) were present in the “in situ” component. Conclusion: Conclusion: AGMLG are still unfamiliar entities that can be mistaken for metastatic adenocarcinomas. The “in situ” com- ponent remains the best mean to establish the origin of the lesion. The case we presented emphasizes the importance of recognizing AGMLG and their potential of malignization, which can aid in early diagnosis, appropriate management and avoid overtreatment. E-PS-06-074 Correlations between main morphological features of gastric carcinomas I.E. Ple ș ea*, A. Ciobănoiu, R.M. Plesea, R.N. Ciurea, V.T. Grigorean, V.E. Strâmbu, F. Gherghiceanu *Doctoral School, “Carol Davila” University of Medicine and Phar- macy, Bucharest, Romania, Department of Pathology, “Bagdasar- Arseni” Emergency Clinical Hospital, Bucharest, Romania Background & objectives: Gastric carcinomas (GC) were the fifth most common malignancy and the third cause of malignancy deaths worldwide. They were heterogenous concerning phenotype, genotype, clinical and prognostic behaviour. The study aims to compare six main morphological and behavioural features of GC. Methods: A series of 75 GCs were grossly examined and stained with Masson’s trichrome, silver impregnation (Gömöri technique), and immune-stained with Smooth-Muscle Actin, CD34 and Ki67. The assessed parameters were: gross aspect (Bormann scale), tumour grade, local invasion (pT), stroma amount, vascular density (VD), and aggressiveness (Ki67 index). Each parameter was scaled individually and specifically. Results were compared using chi-square test. Results: Gross aspect had no statistical correlation with none of the other parameters (chi-square test ”p” values > 0.05). The same situation appeared when tumour grade, local invasion, stroma account, VD and tumour aggressiveness were compared each to each. However, ”p” value of chi-square test was around 0.1 when compared tumour grade with gross aspect, local invasion, and intratumor vas- cular density (0,284, 0,13, and 0,134 respectively), indicating a mild tendency of correlation between the respective parameters. Conclusion: Our data revealed no obvious trend of correlation between main morphological and behavioural features of studied gastric epithe- lial malignancies, excepting some correlation trend between tumour grade, on one hand, and local invasion and intratumor vascular net- work, on the other hand. E-PS-06-075 Chromogranin A overexpression in the colonic mucous of patients with slow-transit constipation: clinical case series M. Plodiienko*, S. Nikolaienko, P. Byk, I. Lieshchyshyn, T. Amalyan, S. Gychka *Bogomolets National Medical University, Ukraine Background & objectives: Slow transit constipation can cause seri- ous physical and social disability. Since total colectomy may be the last treatment option, it is important to clearly identify its indications. This study focuses on the imbalance of neuroendocrine markers in the colonic mucosa. Methods: Formalin-fixed, paraffin-embedded post-colectomy samples of sigmoid colon from 3 patients were studied with light microscopy and immunohistochemistry, IHC, (chromogranin A, synaptophysin). Levels of expression of chromogranin A and synaptophysin were esti- mated in myenteric plexus. Number of neuroendocrine cells in mucosa were counted in 15 HPF (0,24 mm2) for two markers separately. Results: All patients presented with similar histological changes: focal sing of neuronal damage in myenteric plexus (red cyroplas- mic inclusions, swelling of neuranal bodies); lymphoid follicular hyperplasia and increased number of lymphocytes in lamina propria. Immunohistochemically, an increase in the number of chromogranin A positive cells was defined in the crypts with a marked intensity of expression of its (206, 201, 194 positive cells/15 HPF). The expres- sion of synaptophysin did not demonstrate this pattern in mucosal crypts. Analysis of the expression of chromogranin A and synap- tophysin in myenteric plexuses demonstrated their decrease in only one of three cases.