ECP 2022 Abstract Book

Virchows Archiv (2022) 481 (Suppl 1):S1–S364 13 C. Dahlstedt-Ferreira*, D. Argyropoulou, P. Marta, P. Marques, H. Oliveira Coelho *Hospital Garcia de Orta, E.P.E, Portugal Background & objectives: Acinar cell carcinomas are rare malig- nant epithelial neoplasms, arising from the exocrine acinar tissue, with poorly defined pathogenesis. Males are more commonly affected and presenting symptoms are related to tumour growth. We present a case report on this rare entity. Methods: We received a fine-needle aspiration (FNA) sample from a 57 year-old man with a pancreactic isthmic mass. On endoscopic ultrasound, a 5,8cm lesion, partially solid and partially cystic was found, without signs of vascular invasion or signs of regional lymph node metastasis. We performed the analysis on stained sam- ples with PAP, MGG and a cellblock. Results: The sample was moderately cellular, with red blood cells and trabecular formations, with pseudorosette formations, syncyt- ial cytoplasm with round and monotonous nuclei, with occasional nucleoli. Mitosis figures were observed and necrosis was absent. On cellblock evaluation, immunohistochemistry was performed. The lesion was positive for CK AE1/AE3, CK7, Trypsin, PAS/D and negative for CK20, CD56, NSE, Synaptofysin, Chromogra- nin, Beta-catenin (membrane staining). This was compatible with a pancreatic acinar cell carcinoma (Category VI – Malignant, The Papanicolaou Society of Cytopathology System for Reporting Pan- creatobiliary Cytology). Conclusion: Acinar cell carcinoma has a poor prognosis, with approximately 50% of the patients have metastatic disease at presentation and a 5-year survival rate of 25%. Although aggressive, it appears to have a better prognosis than conventional pancreatic ductal adenocarcinoma. It is a rare entity without any hallmark genetic alteration, and we present this case to shed a light on the importance of immunohistochemistry and markers like trypsine while diagnosing this type of lesions, as well as the morphological aspects. E-PS-05 | E-Posters Dermatopathology E-PS-05-001 Pure bullous pyoderma gangrenosum, a challenging clinico- pathological diagnosis - critical literature review with emphasis on diagnostic criteria P. García Abellás*, B. Díaz Guimaraens, A. Ferrer Gómez, R. Car- rillo Gijón *Ramón y Cajal University Hospital, Spain Background & objectives: Pyoderma gangrenosum is an uncom- mon neutrophilic dermatosis characterized by large necrotic ulcers. Occasionally patients develop atypical presentations, including bullous lesions. Only eighteen pure cases of Bullous Pyoderma gangrenosum have been described. Our aim is highlight distinctive clinical and patho- logical features. Methods: We describe a case of Bullous pyoderma gangrenosum in a 76-year-old man, with active oncological history, including a recent diagnosis of hairy cell leukaemia. We have carried out an exhaustive review of the literature where clinical and pathological details of the lesions are absent or very scant. Furthermore, many of the cases reported were mixed variants. Results: Clinically, our case supposed a challenging differ- ential diagnosis due to atypical clinical presentation that mim- icked necrotizing fasciitis. The purple blistering appearance of the lesions in the setting of a patient with multiple treatments, raised the possibility of an adverse drug reaction. Nevertheless, the exacerbation of the large plaque after surgical procedures was a clear sign of pathergy. Histologically, there was partial preserva- tion of the epidermis, subepidermal vesiculation and neutrophilic exocytosis. A massive neutrophilic infiltrate filled the dermis and hypodermis without vasculitis or any sign of specific infection. The patient was treated with diverse intravenous antibiotics and several surgical procedures without improvement. Finally healed after gradual weaning from immunosuppressive therapy. Conclusion: The variety of clinical manifestations and it´s non- specific histology, make Bullous pyoderma gangrenosum a chal- lenging diagnosis. A good clinicopathological correlation, always in the setting of complementary tests, it´s crucial for accurate the diagnosis. This case highlights the importance of maintaining a strong clinical suspicion in a patient with rapidly progressive, non- infectious blisters that worsens after surgical procedures in the context of an hematologic disorder and G-CSF treatment (described as possible triggers). E-PS-05-002 Telangiectasia arising in submandibular melanocytic (com- pound) nevus M. Givannakis, D. Anestakis*, G. Tsiropoulos, C. Charalampidis, N. Krystalidis, I. Dimitriadis, P. Karkos *Laboratory of Pathology, Forensic Service of Thessaloniki, Greece Background & objectives: Telangiectasia is an excessive permanent dilation of superficial blood vessels in the skin. The development of telangiectasia in the final blood vessels of dermal tumours is uncom- mon. The characteristics of the lesion are described and a literature review is attempted. Methods: We present a case of a 16-year-old woman who reports the presence of a dark spot on her submandibular area for years. The last six months report alteration of the mole hue, mainly in the central areas. The dermatological examination shows a round lump with clear peripheral boundaries and a brownish uneven appearance and a surgical removal is decided. Results: The surgical specimen consists of a fusiform part of skin with a surface of dimensions 1.5X1 cm and a thickness of 0.8 cm. In the middle of the free surface there is a hemispherical protrud- ing dark skin formation (tumour) with a larger diameter of 0.8 cm. Histologically it shows an image of a compound nevus, in the central area of which lesions compatible with telangiectasia are found. In particular, dilated thin-walled vessels are found, which do not form a formation but grow between the cells of the nevus, and their lumen is filled with blood elements. Conclusion: Telangiectasia can be an isolated phenomenon or as part of a generalized disorder. Secondary development may be caused by external forces such as scratching, trauma, radiation, infection etc. The distinction between a primary and a secondary lesion is not always clear. The bleeding is considered the most important complication of the lesion and when it develops in dermal tumours it causes unusual macroscopic alterations of the structure in which it grows, which can create clinical differential diagnostic problems. E-PS-05-003 Intersticial Mycosis Fungoides. A clinicopathologic study of four cases A. Córdoba*, G. de Lima, A. Pasco, A. Larrea, D. Guerrero, J.I. Yanguas *Complejo Hospitalario de Navarra, Spain S206