ECP 2023 Abstracts

S262 Virchows Archiv (2023) 483 (Suppl 1):S1–S391 13 was approximately twice as high in MMR-intact (n=12/19, %63,2) than in the MMR-d cases (n=4/11, 36,6%). Conclusion: According to our single-centre data in the Turkish popula- tion, the ratio of MMR-d cases among EECs seems to be in line with the literature. There were no statistically significant clinicopathologi- cal differences in MMR-d and MMR-intact tumours. The number of patients in our study is small, we believe that once reflex testing is implemented in all centres in Turkey, more accurate data will be avail- able. In our clinic, this is a preliminary study of incidence and statistics of MMR-d endometrioid-type adenocarcinomas. E-PS-10-038 Immunohistochemical expression of CD47 and its potential role in endometrial carcinoma M. Lambropoulou*, V. Papadatou, S. Polychronidou, S. Tologkos, C. Alexiadi, T. Deftereou, T. Alexiadis, C. Nikolaidou, V. Lampro- poulou, G. Tripsianis *Histology-Embryology Lab., Medical Department, Democritus Uni- versity of Thrace, Alexadroupolis, Greece Background & objectives: CD47 is a transmembrane protein expressed in various cells, that binds with SIRPa ligand of mac- rophages workings as a “don’t eat me” signal. CD47 is overexpressed in many malignancies. We aimed to evaluate its correlation with endo- metrial carcinoma. Methods: Forty-two (42) paraffin-embedded endometrial tissues were studied. Thirty-two (32) of them were endometrial cancer sam- ples (study group) and the other 10 (control group) came from total hysterectomies without malignancies. CD47 expression was studied via indirect immunohistochemistry using a monoclonal anti-CD47 antibody. The expression was then statistically correlated with variant clinicohistopathological parameters. Results: Our results showed that CD47 expression was more posi- tive in patients’ tissues compared to controls’ (p<0.001). The associa- tion of CD47 expression with clinicopathological parameters revealed that higher CD47 expression was associated with ages older than 60 (p<0.001), invasive carcinomas (p<0.001), moderate or poor differ- entiation (p<0.001) and advanced stages (p<0.001). Patients with moderate or high CD47 expression were more likely to die of cancer compared to those with negative or low CD47 expression (94.4% vs 0%, p<0.001). Multivariate logistic regression analysis revealed that higher age (p=0.049) and invasive carcinomas (p=0.009) remained the two independent determinants for moderate or high CD47 expression in women with endometrial carcinoma. Conclusion: Our research demonstrated a clear correlation between the overexpression of CD47 in endometrial malignancies and worse clinical and histological parameters. Our results indicate that CD47 overexpression can provide the tumour with resistance to phagocytosis. However, more studies are needed to establish these results, as CD47 seems a useful prognostic factor as well as a predictive therapeutic target for patients with endometrial carcinoma. E-PS-10-039 Pure uterine lipoma – case report of a rare benign entity presenting as a fast-growing tumour Ž. Ledinek*, B. Ninković Krstonošić, T. Bujas *Department of Pathology, University Medical Centre Maribor, Slovenia Background & objectives: Pure uterine lipoma is a rare subtype of the lipomatous tumours of the uterus that include lipofibroma, angio- myolipoma, liposarcoma and others. There are few reported cases, all occurring in postmenopausal women presenting with abdominal mass, abdominal pain, or postmenopausal bleeding. Methods: We present a case of a 74-years old woman with a fast- growing tumour of the uterine corpus which recently increased in size. Due to the patient’s medical history of postmenopausal bleeding and her family history of cancer, laparoscopically assisted vaginal hyster- ectomy with bilateral adnexectomy was performed. Only gynaecologic ultrasound but no other imaging was done preoperatively. Results: Gross examination of hysterectomy specimen revealed sub- mucosal, well circumscribed, completely encapsulated mass of fatty tissue without solid areas, measuring 6,4 cm in its greatest dimension. Microscopically the tumour was composed of islands of mature adipo- cytes intersected by thin fibrous septa with no elements of atypia. No additional immunohistochemical methods were necessary to define the lesion as a pure uterine lipoma. Histological examination of the uterine corpus also showed atrophic endometrium with foci of endometrial glandular hyperplasia without atypia. Conclusion: Pure uterine lipomas are extremely rare with an estimated incidence of 0,2–0,03% and this is the first documented case in Slo- venian population. Little is known of their origin and tumorigenesis. Since they are benign and can be diagnosed on an MRI or CT scan, it is important to consider conservative management for women with no significant symptoms to prevent unnecessary surgery. They can coexist with other, also malignant conditions or cause alarming symptoms, and are therefore often surgically removed anyways. E-PS-10-040 Metastatic low-grade endometrial stromal sarcoma initially pre- senting as a shoulder lump W. Lee*, Y.M. Lee *Dankook university college of medicine, Republic of Korea Background & objectives: Low-grade endometrial stromal sarcoma is a relatively indolent sarcoma. It is characterized by frequent, late and slow-growing tumour recurrences. The tumour relapse is common in the pelvis, followed by abdomen, vagina, lung, liver, heart and bone. Methods: A 79-year-old female patient was transferred from an outside clinic for a management of a recurrent shoulder lump. Six months ago, the patient underwent an excision of a shoulder lump at the outside clinic that has been recurred recently. The patient’s past medical history was unre- markable except for a gastrectomy due to early gastric cancer 20 years ago. Results: MR shoulder revealed a 5 cm-sized lobulated mass at the subcutaneous tissue of right shoulder. The patient underwent a wide re-excision of the mass. Macroscopically, a multinodular fish-flesh soft mass was noted at the subcutis and dermis. Microscopically, the mass showed a sheet of monotonous short-spindle cells with scant cyto- plasm and frequent mitotic figures. The vasculature was distinctive and comprised of thin arteriole-sized vessels. Immunohistochemically, tumour cells were diffusely and strongly positive for vimentin, CD10, WT-1 and caldesmon, and they were weakly positive for progesterone receptor (PR) and oestrogen receptor (ER). A diagnosis of metastatic low-grade endometrial stromal sarcoma was made. Conclusion: In conclusion, we reports a rare case of metastatic low- grade endometrial stromal sarcoma that initially presented as a solitary shoulder lump without a previous history of intrauterine tumour. E-PS-10-041 Features of COX2 expression in endometrial carcinomas M. Lyndin*, O. Kravtsova, K. Sikora, Y. Bova, Y. Sikora, Y. Lуndіna, N. Hyriavenko, A. Romaniuk *Sumy State University, Ukraine Background & objectives: Uterine corpus cancer is a highly prevalent gynaecologic malignancy, with endometrial cancers (EC) accounting for approximately 90% of cases. The prognosis of EC is determined by the histological type of carcinoma, the qualitative characteristics of the neoplastic cells and stroma. Methods: The investigation was conducted on 50 cases of EC, includ- ing 30 cases of endometrioid endometrial carcinomas (EEC), 10