ECP 2023 Abstracts

S253 Virchows Archiv (2023) 483 (Suppl 1):S1–S391 13 Conclusion: The case we present showcases two rare disease variants that pose unique diagnostic challenges due to either their gross or micro- scopic appearances. To our knowledge, there are less than 100 cases of CDL reported to date and cases of mitotically active thecoma are even scarcer. Therefore, we highlight the importance of histopathology in the diagnostic procedure of surgical specimens as well as the importance of avoiding overdiagnosis of unusual aspects in such tumours. E-PS-10-005 Prognostic significance of GATA4 in adult type granulosa cell tumour of the ovary D. Arik*, I. Bağcı, E. Telli, T. Öge, Ö.T. Yalçın *Eskisehir Osmangazi University, Turkey Background & objectives: The aim of the study is to determine the expression level of GATA4 in adult type granulosa cell tumours, to determine its relationship with clinicopathological features and to reveal its effect on survival. Methods: GATA4 expression level was determined immunohisto- chemically in granulosa cell tumour cases diagnosed in our depart- ment. It was investigated whether there was a significant relationship between expression level, clinicopathological parameters, recurrence and survival. Results: GATA4 expression level was found to be higher in early stage cases. GATA4 expression level was not associated with overall survival or disease-free survival. The only consistent prognostic parameter asso- ciated with prognosis was FIGO stage. Conclusion: GATA4 expression supports good prognostic features. Expression level does not affect survival time and is not related to other clinicopathological parameters. It is necessary to reveal the parameters that can be used to predict prognosis and recurrence. GATA4 could be a potential marker here. E-PS-10-006 How far can a metastasis of squamous cell carcinoma of the uterine cervix spread? S. Aviel-Ronen*, A. Dobriyan, S. Felder, E. Akerman, I. Gluck, M. Vered *Adelson School of Medicine, Ariel University, Pathology Department, Sheba Medical Center, Tel Hashomer, Israel Background & objectives: Cervical carcinoma commonly spreads locally and to regional lymph nodes. Here we describe an unusual case of cervical squamous cell carcinoma that at diagnosis presented with metastasis in the mandibular condyle. Tumour origin was ascertained by immunostains and molecular studies. Methods: The medical records, imaging tests, pathological find- ings and molecular studies of the patient have been studied and are presented. Results: A 55 years old female patient presented with post-coital bleed- ing. On gynaecological examination a 5 cm cervical mass was found, sampled and diagnosed as squamous cell carcinoma. MRI revealed local spread to the uterine isthmus, left cervical fornix and regional lymph nodes. PET-CT demonstrated an additional hypermetabolic focus in the left mandibular condyle. Despite normal and functional physical examination, an incisional condyle bone biopsy revealed squa- mous cell carcinoma metastasis. The carcinoma cells were positive for p16 immunostain and HPV in-situ. HPV typing was done using Master Diagnostics HPV Direct Flow CHIP on the eBRID automated system and HPV 16 and 6 were detected, confirming the cervical origin. Conclusion: Squamous cell carcinoma of the uterine cervix might metastasize even to unusual and distant locations, such as head and neck region, without further bone spread. High index of suspicion and a thorough workup of cervical cancer patients are warranted to diagnose and treat early lesions before they become symptomatic and ensure detection of any far metastatic spread. The combination of immunostains and molecular studies is capable of determining cervi- cal origin even in technically challenging tissues such as bone biopsies. E-PS-10-008 Recurrent ovarian tumour with PTCH1::GLI1 fusion and loss of FOXL2 copy number: a case report of a neoplasm mimicking sex cord stromal tumour R. Bakkar*, M. Afkhami, M. Song, R. Ali-Fehmi, H. Maluf, D. Bell, A. Malpica *City of Hope National Cancer Center, Department of Pathology, USA Background & objectives: GLI1-altered neoplasms encompass a rare heterogeneous group of tumours, reported in the oral cavity, soft tissue, and gastrointestinal, genitourinary and gynaecologic tracts. We report the first case of an ovarian tumour with PTCH1::GLI1 fusion and loss of FOXL2 copy number. Methods: A 70-year-old female with history of unclassified right ovar- ian sex-cord stromal tumour (2010), initially treated with right sal- pingo-oophorectomy, followed by multiple pelvic recurrences treated with multiple debulking surgeries, chemotherapy, and radiotherapy. She presented in 2023 with recurrence in the liver, abdominal wall, and pelvis for cytoreduction. Grossing, routine laboratory processing, immunohistochemical studies and comprehensive next generation sequencing (NGS) were performed. Results: The tumour masses were haemorrhagic and fleshy. Histo- logically, the tumour had multinodular growth, prominent vascularity, oedema and focal myxoid changes in the stroma. There was a combina- tion of architectural patterns: nested, trabecular, solid, cystic and folli- cular spaces filled with eosinophilic material. The cells were epithelioid, monotonous, with eosinophilic/clear cytoplasm and small oval nuclei, with mild to moderate atypia, variable grooves, and focal vesicular chromatin, mitotically active, without necrosis. The tumour cells were diffusely positive for SF-1, and CD56, and patchy weakly positive for CD10, D2-40 and S100 while negative for SOX10, pancytokeratins, EMA, synaptophysin and chromogranin. BRG1 expression was retained. NGS detected PTCH1::GLI1 fusion and loss of FOXL2 copy number. Conclusion: This case is the first reported to carry PTCH1::GLI1 fusion and loss of FOXL2 copy number. Some shared features with other GLI1- altered tumours may suggest commonality. Recognizing the occurrence of this entity in the gynaecologic tract is important, given the availability of targeted therapy involving the SHH-GLI1 pathway, GLI1 inhibitors, and tyrosine kinase inhibitors. Although the clinical significance of loss of FOXL2 copy number is unclear, its presence suggests loss of function. E-PS-10-009 Ovarian teratoid carcinosarcoma, a case report with SMARCA4 loss R. Bakkar*, M. Afkhami, J. Cohen, R. Ali-Fehmi, L. Arvanitis, A. Malpica, D. Bell *City of Hope National Cancer Center, Department of Pathology, USA Background & objectives: Ovarian teratoid carcinosarcomas (TCSs), with immature neuroepithelium, with or without germ cell component, reminiscent of sinonasal tract TCSs, are extremely rare, with debatable origin- True germ cell versus pluripotential stem cell. We describe the first ovarian case with SMARCA4 loss. Methods: A 73 y.o. female presented with postmenopausal bleeding, 6.1 cm solid right ovarian mass by imaging and elevated CA-125, treated with total abdominal hysterectomy, bilateral salpingo-oophorectomy and debulking surgery at an outside hospital, diagnosed with ovarian carcino- sarcoma with heterologous chondrosarcoma elements, FIGO IIIB. Slides were reviewed in consultation, additional immunohistochemical studies and comprehensive next generation sequencing (NGS) were performed.