ECP 2023 Abstracts

S197 Virchows Archiv (2023) 483 (Suppl 1):S1–S391 13 Among the information collected we included sociodemographic and clinical data. Hematoxylin & Eosin, Silver, Grocott, Fite-ferraco and PAS stains were performed in the appendiceal samples. A review of the existing literature was carried out. Results: We included 3 patients (2 males). The age range was 29-73 years. Clinically, one patient presented as a complicated acute appendicitis (AA), other as a non-complicated AA and the last one followed a subacute course. All patients had leukocytosis and neutrophilia. All patients had radiological studies compatible with AA. Intraoperatively, 2 of the patients presented an inflammatory plastron and other a gangrenous AA. AA was histologi- cally confirmed in two cases. Actinomyces colonies were identified and confirmed by different stains in all cases. Two of the patients received antibiotherapy for less than 2 weeks while one patient was treated for 12 months. All patients evolved favourably and did not present recurrences. Conclusion: Appendiceal actinomycosis is an infrequent pathology whose clinical presentation can be very variable. In our experience, 2 cases presented clinically as AA and all patients evolved favourably with surgery and empiric antibiotherapy. Future studies that characterize this entity in diagnostic, therapeutic and prognostic terms are required. E-PS-06-016 Retrospective case series analysis of patients with inflammatory bowel disease: a laboratory experience in Northeast of Brazil J. Carneiro Melo*, H. Neves Feitosa Filho, N. Pinheiro Rodrigues, R. Vilar Lima, A. de Carvalho Assunção, G. Ferreira Morgantetti, G. Alencar Medeiros, D. Nunes Oliveira *Univesity of Fortaleza, Brazil Background & objectives: Inflammatory bowel diseases (IBD) are chronic conditions characterized by inflammation of the digestive tract, including Crohn’s disease and ulcerative colitis. Symptoms include abdominal pain, diarrhoea and weight loss. Aims to examine the histo- pathological findings in biopsy reports obtained from patients with IBD. Methods: A retrospective and descriptive study of histopathological reports of patients with suspected inflammatory bowel disease, carried out in the Pathology laboratory, in northeastern Brazil, from January 2018 to March 2023.This study included analysis of cases of Crohn’s Disease, ulcerative colitis according to the definition criteria estab- lished by the European guidelines of gastroenterology. Results: A total of 520 histopathological reports were compatible with inflammatory bowel disease (IBD), the average age was 39,32 years and 60% (312) of the patients were women. Crohn’s disease (CD) rep- resented 60% (313) of IBDs, ulcerative colitis (UC) was responsible for 39% (203) of the cases and the diagnosis of nonspecific colitis was given in 0,7% (4) of the cases. Granulomas were seen in 15% (47) of CD and Cryptic abscess were reported in 37% (75) of the cases of UC. Low grade dysplasia was found in 1% (6) cases and a concomitant adeno- carcinoma was observed in 0,3% (2) of the reports, both in CD patients. Conclusion: Our results demonstrated that the patients were predomi- nantly female, and CD was more prevalent than UC in this series of cases in Northeast Brazil. Accurate histopathological diagnosis, with differentiation between inflammatory bowel diseases, is important for the proper treatment and management of IBD. E-PS-06-017 Unusual cutaneous metastases from colon adenocarcinoma J. Carneiro Melo*, Á. Macêdo Freire, G. Carvalho de Freitas Soares, B.R. Novais Lima, S. Samuel Feitosa Machado, C. Gleidiston Lima da Silva *Univesity of Fortaleza, Brazil Background & objectives: Adenocarcinoma is the main histological type of colorectal cancer with increasing incidence and high morbid- ity and mortality. Cutaneous metastasis of this malignancy is rare, approximately 5% of cases. Report a rare case of metastasis of sigmoid adenocarcinoma in the skin. Methods: We present the case of an 80-year-old man with a previous diagnosis of sigmoid adenocarcinoma 8 years ago, who underwent rec- tosigmoidectomy in 2014, progressing progressively to jaundice, recur- rent hematemesis, ulcerated lesion on the right shoulder and death. At autopsy, an incisional biopsy of the lesion was performed. Results: The microscopy showed cytoarchitectural distortion of the cutaneous tissue, large necrotic areas due to the advanced stage of the lesion and presence of sparse goblet cells. The development of cutane- ous metastases in the course of visceral malignancy is an indicator of poor prognosis, they tend to occur in advanced stages of the disease and close to the site of the primary tumour, the abdominal skin being the most common region, due to contiguity or, more rarely, surgical implantation. Cutaneous metastases distant from the primary site, as presented in this case, are infrequent and the literature points out that they can be explained by haematological or lymphatic dissemination of malignant cells. Conclusion: Cutaneous metastases from colon adenocarcinomas repre- sent a challenge in clinical practice, since their detection requires a high degree of clinical suspicion. Early recognition and timely diagnosis are essential for the best survival rate. The reported case emphasizes that skin lesions with progressive growth or that do not heal after con- ventional therapy, may be the first manifestation of a new metastasis, as in the present case, or rarely be the first manifestation of advanced visceral cancer. E-PS-06-018 Mixed neuroendocrine-non-neuroendocrine neoplasm (MiNEN) of the ascending colon in a middle-aged female patient: a case report on a rare entity G. Carrola*, A.P. Rodrigues, D. Sá, F. Sousa Vieira, J.R. Vizcaíno, N. Jorge Lamas *Centro Hospitalar Universitário de Santo António, Portugal Background & objectives: A mixed neuroendocrine-non-neuroendo- crine neoplasm (MiNEN) contains dual neuroendocrine and non-neuroen- docrine components, with each component representing at least 30% of the tumour. It is an extremely rare neoplasia, scarcely reported in the colon. Methods: We report the case of a 62-year-old female patient who came to the emergency service with an acute episode of bowel obstruc- tion. The CT scan study revealed the presence of an ascending colon tumour with probable perforation. The patient was submitted to right hemicolectomy. Results: Macroscopic examination revealed a 5cm vegetant tumour in the right colon, with infiltration of the muscularis propria and extension to the pericolic fat. Histological analysis revealed a MiNEN, composed of a 60% moderately differentiated adenocarcinoma component with mucinous areas and a 40% large cell neuroendocrine carcinoma com- ponent. Immunohistochemistry showed positivity for CK20, CDX2 and SATB2 on both components and for chromogranin A, synaptophysin and CD56 on the neuroendocrine component. The proliferative index was ≈60% and NGS analysis revealed a KRAS mutation. Eight out of the 16 isolated lymph nodes had metastasis. Progression of disease occurred, despite adjuvant chemotherapy, with lung and liver metasta- tization. The patient passed away after 7 months. Conclusion: This case highlights the main features of the extremely rare mixed neuroendocrine-non-neuroendocrine neoplasm (MiNEN) of the colon. Some factors associated with worst prognosis are a high tumour grade, an increased number of gene mutations, and advanced- stage disease, as well as a large percentage of the neuroendocrine com- ponent. It is important to emphasize the very aggressive biological behaviour of this neoplasia, which usually portends a dismal survival, similarly to what happened with the patient.