ECP 2022 Abstract Book

Virchows Archiv (2022) 481 (Suppl 1):S1–S364 13 predominantly capillary vascular proliferation without atypia was identified, with a multinodular arrangement, partially involving the adjacent parenchyma comprised of serous salivary glands showing signs of atrophy. There were occasional thrombi and signs of old and recent bleeding. The immunohistochemical study supported the diag- nosis of haemangioma (CD34+, CD31+, Podoplanin-, AE1/AE3-, Smooth muscle actin-, HHV-8-). Conclusion: We highlight the importance of considering hae- mangiomas in the differential diagnosis of parotid tumours of adults. These are not usually considered due to their low preva- lence in this population and are normally approached through FNA. This most often results in non-diagnostic aspirates, and ideally should be avoided to prevent iatrogenic hematomas. Diag- nosis depends on integration of clinical and radiological data. When suspected, the patients should undergo early conservative surgery and a final diagnosis made on the surgical specimen. E-PS-11-039 Rhinocerebral mucormycosis: a report of 11 cases M. Ben Thayer, F. Khanchel, I. Helal, S. Elfekih*, R. Hedhli, E. Ben Brahim, R. Jouini, A. Chadli *Habib Thameur Hospital, Tunisia Background & objectives: Mucormycoses are rare aggressive fungal infections that are rapidly extensive and usually fatal. Rhinocerebral mucormycosis is the most common form. We aim to study the clinical and anatomopathological aspects of this rare and life-threatening entity. Methods: We retrospectively studied all cases of rhinocerebral mucormycosis diagnosed at Habib Thameur’s hospital over a period of 13 years (from 2008 to 2020). Only cases confirmed by pathological examination were included in our study. Results: Our sample consisted of 11 cases. They were eight men (72.7%) and three women (27.3%) with a sex ratio of 2.66. The age of the patients varied between 12 and 78 years with an average of 45 years ±18.62. In this study, eight patients were immunocompromised. One patient was on long-term corticosteroid therapy for systemic lupus erythematosus, the 12-year-old patient had bone marrow aplasia, three patients were diabetics, one patient had acute myeloid leukaemia, one patient had IgM type immunodeficiency and one patient had lymph node tuberculosis. Two of our patients had orbital cellulitis, only one patient had proptosis and all the other patients had acute sinusitis. Conclusion: Rhinocerebral mucormycosis is a rare and under- diagnosed pathology. Its diagnosis is often challenging. It is a medico-surgical emergency. The diagnosis of certainty is based on pathological examination. Its management is based on surgery and antifungal treatment.It has poor prognosis with high morbidity and mortality rates. An early diagnosis is crucial and allows the rapid onset of appropriate treatment. A better knowledge of this pathology and its evocation, especially in immunocompromised patients, would improve the prognosis and survival rates. E-PS-11-040 Adenomatoid hyperplasia of minor salivary glands - a case report E. Caranfil*, C. Cucu, A. Nicolau, D. Ciobanu-Apostol *Spitalul Clinic Judetean de Urgenta "Sf.Spiridon", Iasi, Serviciul de Anatomie Patologica, Romania Background & objectives: Adenomatoid hyperplasia of minor sali- vary glands is a rare lesion occuring predominantly in the palate with some rare cases described in the buccal mucosa. It is of unknown aeti- ology and imitates a salivary gland tumour. Methods: A 60-year old man presented to the hospital for dys- phagia and a 5 cm palatal mass was discovered. A biopsy was performed which came back as squamous cell carcinoma in situ. The mass was resected and was sent to the pathology department. Grossly the mass was covered by regular, smooth mucosa and resembled salivary gland parenchyma on the cut surface. Results: Microscopically, scar tissue corresponding to the biopsy was identifiable. The epithelium presented pseudoepitheliomatous hyper- plasia without dysplasia. The submucosa corresponded to mucous type acini with lobular architecture, separated by fine connective tis- sue bands. Rare ducts were identifiable as well as extracellular mucus. No dysplastic or malignant features were present. Inflammation was minimal; predominantly lymphocytes and plasmocytes were appreci- ated. The surgical resection margins were in contact with the acini. Conclusion: Adenomatoid hyperplasia of the minor salivary glands is a rare benign lesion which can be cured by complete surgical resection. The clinical appearance can be in favour of a salivary gland tumour, therefore a biopsy is required in order to properly classify the lesion. E-PS-11-041 Oral carcinoma cuniculatum: a diagnostic challenge N. Arı*, Ç. Oysu, L. Cinel *Marmara University School of Medicine, Department of Pathol- ogy, Turkey Background & objectives: Carcinoma cuniculatum (CC) is a variant of squamous cell carcinoma characterized by crypt-like structures of squa- mous epithelium with minimal atypia. Given its rarity and lack of atypia, it has been a diagnostic challenge. We present a mandibular case of CC. Methods: Forty eight-year-old male patient presented with left mandibular pain lasting for 1,5 years. Multiple incisional biopsies showed almost no sign of malignancy, except minimal cytologic atypia and burrow-like growth pattern. However, the last incisional biopsy was diagnosed as squamous cell carcinoma, considering radiologically detected extensive bone destruction. The patient underwent left hemimandibulectomy and ipsilateral cervical lymph node dissection. Results: Macroscopic evaluation of the resection specimen revealed no distinct mass lesion, although some areas of the man- dible were easy to cut. Histopathologic examination revealed a lesion which consisted of keratin-filled crypt-like structures lined by well differentiated squamous epithelium which showed multi- ple foci of microabscesses and almost no cytologic atypia. Crypt- like structures were extending deep into the underlying bone in a destructive fashion, suggesting a malignant process. No metastatic lymph node was observed. Immunohistochemistry results for p16 and HPV were negative. All these findings taken into considera- tion, the case was concluded to be compatible with CC, which is a very rare variant of squamous cell carcinoma. Conclusion: This local aggressive histologic variant of squamous cell carcinoma remained under-diagnosed because of its extremely well differentiated nature and rare incidence. Some percentages of the cases are being reported as verrucous carcinoma (VC), since both entities show minimal cytologic atypia. However, unlike CC, VC shows invasion in a pushing manner. Very rare cases with lymph node and distant metastases have been reported. Our case report aims to raise awareness of such entity among pathologists and prevent misdiagnosis of this disease. E-PS-11-042 Primary mucosal melanoma of the nasal cavity, report of 5 cases Z. Lajmi*, T. Tlili, S. Mabrouk, Y. Fejji, B. Sriha, M. Mokni S290