ECP 2022 Abstract Book

Virchows Archiv (2022) 481 (Suppl 1):S1–S364 13 Results: 402 mediastinal lymph node FNA were performed. 69% male. Mean age 65 years old (range 19 - 90). Mean number of passes 3.14 (range 1 - 8). Mean procedure time 25.33 minutes (range 10 - 90). Mean number of cytological smears 13.03 (range 3 - 38). Sydney System first level diagnostic categories: I: 4.48%; II: 36.82%; III: 0%; IV: 0%; V: 58.71%. Immediate sample man- agement (microbiology, molecular tests, flow cytometry, etc.) was necessary in 33% of cases. The most frequent diagnosis of malignancy was metastatic lung carcinoma (218 patients - second diagnostic level). Conclusion: To date, few scientific publications have high- lighted the usefulness of the Sydney System in the categoriza- tion and diagnosis of lymph node FNA. The results obtained (with less than 5% of insufficient samples) support the appli- cability of this classification system in samples obtained by EBUS-TBNA. We consider the modified touch imprint cytology plus ROSE methodology (which allows validation of the repre- sentativeness of the cell block) to be a key step in achieving the results obtained. PS-12 | Poster Session Dermatopathology PS-12-001 Cutaneous metastases from non-primary skin tumours I. Bernal Simón*, Y.P. Rodríguez Velandia, N.M. Segués Merino, M.A. Juaristi Abaunz, M.Y. Silva Carmona *Donostia University Hospital, Spain Background & objectives: Cutaneous metastasis (CM) accounts for only 2% of all skin neoplasms. They occur infrequently and usually during the late stages of cancer with poor prognosis. The objective is to analyse the different types of CM, their location and survival. Methods: We reviewed skin biopsies of cancer patients diagnosed with CM between January 2006 and February 2022 at Donostia University Hospital in Spain. Patients with primary skin cancer and haematological malignancies were excluded. We collected the following data: patient age and sex, the time of cancer diagnosis and CM, location of CM, type of cancer and survival outcome. Results: We included 16 patients, aged between 48 and 93 years (mean 68), of whom 11 were women and 5 men. Breast cancer was the most common primary cancer (6 cases), followed by gastric adenocarcinoma (3 cases) and clear cell renal cell carcinoma (2 cases). Pancreatic ductal adenocarcinoma, neuroendocrine tumour of the lung and arytenoid cartilage, hepatocellular carcinoma and endometrial serous carcinoma were also found. The most frequent locations for CM were head, neck and chest. Although most skin metastases were solitary, patients presented with advanced-stage cancer with other visceral metastases. Only five patients are still alive. Conclusion: Cutaneous metastases have an incidence of 0.7% to 9%. In general, men are more commonly affected than women, and most patients are aged between 50 and 70 years. In our study, women are the most affected patients with breast cancer. The most typical locations were scalp, neck and trunk. Despite CM being a sign of poor prognosis may not always indicate a poor survival outcome and depends on each type of cancer. PS-12-002 Acute generalised exanthematous pustulosis and generalised pustular psoriasis: differential diagnosis in the report of 2 cases C. Faria*, J. Madeira, B. Sepodes, A. Alves, O. Tellechea, J.C. Cardoso *Pathology Unit, Hospitais da Universidade de Coimbra, Centro Hospitalar e Universitário de Coimbra, Portugal Background & objectives: Acute generalized exanthematous pustu- losis (AGEP) and generalized pustular psoriasis (GPP) share clinical and histopathological similarities, and their classification as separate entities or as diseases within the same spectrum remains controversial. We describe two cases highlighting this diagnostic challenge. Methods: Case A: 36 year-old man presented a generalized pus- tular eruption with an erythematous background, especially on the trunk with involvement of the limbs and face, after COVID19 vaccination. Fever and peripheral blood leukocytosis were also present. Case B: 72 year-old man, previously diagnosed with psoriasis, had a widespread eruption of sterile pustules on an erythematous back- ground, without constitutional symptoms associated. Results: Case A. Histopathological examination revealed an acanthotic epidermis with occasional exocytosis of neutrophils, reaching the upper layers and the stratum corneum. There was also focal intraepidermal and subcorneal detachment with haemorrhage, neutrophils and eosinophils. The dermis presented a mixed inflam- matory infiltrate surrounding vascular and neural structures. Direct immunofluorescence showed granular non-specific IgA deposition at the dermal-epidermal junction. Case B: Microscopical examination presented an epidermis with moderate acanthosis, hyperkeratosis, parakeratosis, hypogranulosis and intraepidermal and subcorneal pustules at different stages of development. There was also a dermal mixed inflammatory infil- trate with numerous neutrophils and haemorrhage. Conclusion: Case A was diagnosed as AGEP; despite the overlap with pustular psoriasis, the clinical information, the small intraepi- dermal pustules and eosinophils favour the former diagnosis. The patient was treated with systemic corticosteroids with good result. Case B was compatible with GPP, given the pre-existing diag- nosis of psoriasis and the slightly more pronounced psoriasiform hyperplasia. Despite the high mortality rate associated (30%), our patient had a great response to treatment with acitretin, and a restrict follow-up. PS-12-003 Basal cell carcinoma with trichogerminoma-like areas, a mor- phological and immunohistochemical study in a series of three cases F. Kubba*, I. Logan *Department of Pathology, Ealing Hospital, London North West University Healthcare NHS Trust, United Kingdom Background & objectives: We present three patients with basal cell carcinoma (BCC) incorporating trichogerminoma-like cell-balls presented as slow growing pearly nodules in a 76, 81 and 88-year-old patients on the temple, back and forearm. Two were ulcerated and one was variably pigmented. Methods: Microscopically all BCCs were of nodular subtype. In addition, they showed lobules of epithelioid cells, with a rim of compact cells and central crowded cells expressing concentric whorled nuclei. They were incorporated within the main BCC area. One case showed clefts surrounding these cell balls with increased apoptosis. No significant atypia or increased mitosis was seen. Another showed focal keratinisation. Results: Immunohistochemistry showed positive staining with cytokeratin 5/6 while BerEP4 was diffusely positive in the BCC and negative in trichogerminoma-like area. They were negative for Epithelial Membrane Antigen (EMA). Cytokeratin 20 did S129