ECP 2022 Abstract Book

Virchows Archiv (2022) 481 (Suppl 1):S1–S364 13 7 cases. One rectal tumour was G3. All appendiceal NETs were classified pT1 or pT2 according the 2019 TNM classification. Con- cerning ileal tumours, 2 were pT3 and one pT4. The diagnosis of the two rectal NET was made in biopsy. Metastasis were present in 3 cases (2 rectal tumours and one small intestine tumour) and they were in the liver. Conclusion: Contrary to many studies, the appendix is by far the most common location of NETs in this study. All appendiceal NETs were G1 and G2 and pT1 or pT2. Small intestine and rectal NETs were associated with metastasis and adverse prognostic factors (high grade and stage). We have confirmed the previously published findings that appendiceal NETs are associated with a good prognosis whereas small intestine and rectal tumours are frequently diagnosed at an advanced stage of metastatic disease. E-PS-06-075 Pre-operative staging of rectal neoplasia - a 8-year series of anatomopathological and imagiolocical correlation M. de Brito Pereira*, T. França de Santana, J. Laert, P. Borralho *Pathology Department, Hospital CUF Descobertas, Lisbon, Portugal Background & objectives: The therapeutic approach to rectal neopla- sia is highly dependent on the clinical and radiological TNM staging (T-tumour, N-node, M-metastasis), where magnetic resonance plays a central role in the staging. This study evaluates the concordance between magnetic resonance and anatomopathological assessment. Methods: We performed a retrospective review of all cases of rec- tal neoplasias (n=212) evaluated in our institution between Janu- ary of 2014 to February of 2022. All patients with imagiological evaluation by magnetic resonance and lack of neoadjuvant therapy were considered (n=51). The anatomopathological staging and the imagiological staging were compared and classified as concordant, parcially concordant or discordant. Results: All 51 cases were adenocarcinomas. The average age of the patients was 66,7 years (between 36 - 85 years old), divided into 30 males and 21 females. The overall TNM staging concordance between the anatomopatho- logical and imagiological pre-operative assessment was 35,3% (18 cases). The majority of cases (53,0%, 27 patients) demonstrated a partial concordance. Discordance was present in 11,7% (6 cases) of patients. When evaluating the staging components separately, the tumour depth of invasion (T) was concordant in 72,5% (36 cases). Regarding the evaluation of lymph nodes (N), there was concord- ance in 51,0% of cases (26 patients). Conclusion: The results regarding the isolated evaluation of each staging component were similar to the previously described in lit- erature. Concerning tumour depth of invasion, magnetic resonance imaging presents as an accurate, non-invasive method for staging rectal neoplasias. However, in half the cases the nodal status was not correctly evaluated. The physicians should remain aware of the limitations of pelvic magnetic resonance appraisal, especially in the detection of tumour nodal involvement. E-PS-06-076 A rare case of duodenal mass revealing an unknown hepatocel- lular carcinoma A. Baccouche*, A. Hassine, W. Majdoub, O. Belkacem, s. moussa, A. Bdioui, S. Mestiri, S. Hmissa *Pathology Department, Sahloul University Hospital of Sousse, Tunisia Background & objectives: Hepatocellular carcinoma (HCC) tends to metastasize to extrahepatic organs. Stomach and duodenum involve- ment has been seldom reported. We report a case of duodenal metas- tasis revealing an unknown HCC in a male patient Methods: A 74-year-old man, presented with atypical epigastric pain, asthenia and anorexia. Clinical examination did not reveal any abnormalities. Laboratory tests showed a microcytic hypochromic anaemia. The patient underwent an upper gastrointestinal endos- copy which revealed an ulcerative mass of the duodenal bulb, measuring 3 cm. Multiple biopsies were performed. Results: Microscopic examination revealed a carcinomatous proliferation, within the duodenal mucosa, arranged in solid and trabecular pattern. Tumour cells were polygonal, with abundant eosinophilic granular cytoplasm, nuclear atypia and brisk mitotic activity. The stroma was sparsely inflammatory. Immunohistochemically, tumour cells stained positive for Hep Par 1. The diagnosis of bulbar metastasis of CHC was made and the patient was recalled for more investigations. Conclusion: Gastrointestinal metastases from HCC are rare, with few cases reported in the stomach and duodenum. The suggested mechanism of metastasis is mainly direct invasion of a tumour contiguous with the GI tract. Herein we described a novel case of duodenal metastasis from HCC which presented as GI bleeding E-PS-06-077 Tumour-stroma ratio on the prognosis of colorectal cancer R. Souza da Silva*, F.F.N. Gomes, J.P. Andrade, L.E.d.M. Barbosa, D.S.G. Silva *Universidade Federal da Paraíba, Brazil Background & objectives: Tumour–stroma ratio (TSR) is a histologi- cal feature that reflects the value of the stromal component that sur- rounds cancer cells and represents a potential prognostic factor. This study aimed to investigate the association between TSR and survival in colorectal cancer. Methods: The TSR was evaluated in patients diagnosed with colo- rectal adenocarcinoma.The analysed variables were age, gender, and pathological features according to the WHO classification. The TSR was categorized into 2 groups: ≤50%- low stroma and >50%- high stroma.The association between categorized TSR and survival was analysed using the nonparametric Kaplan-Meier method. Associations between pathological features and overall survival were also verified. Results: A total of 158 patients participated in this study, of which 40% had lymph node metastasis (regional disease). Tumour budding was observed in 22% of patients. Overall survival was associated with the presence of tumour budding (p-value=0.019) and lymph node metastasis (p-value=0.034), with lower survival for these patients. In the analysed sample, 53.8% of colorectal adenocarcimas fall into the high stroma category, and this group corresponded to the death outcome. The survival of patients in the ≤ 50% - low stroma category was higher when compared to patients in the > 50% - high stroma category. Conclusion: The tumour-stroma ratio (TSR) is a promising prog- nostic biomarker in colon and rectal cancer, represents an inde- pendent prognostic factor, such as lymph node metastasis and tumour budding. Stroma-rich colorectal cancers show a lower sur- vival rate compared to low stromal tumours. E-PS-06-078 Prognostic value of immunoscore in colorectal carcinomas I. Helal*, S. Fkih, F. Khanchel, A. Hmidi, R. Hedhli, E. Ben Bra- him, R. Jouini, A. Chadli S237