case_images: PMC6875561_01
case_images: (A) Initial PET scan showing retroperitoneal mass invading inferior vena cava. (B) PET scan showing retroperitoneal mass progression with right hydronephrosis and lung metastasis post 3 lines of chemotherapy.
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case_images: F0001
case_images: May 2016, when she presented with few months' history of abdominal pain and rising CA 125. MRI and PET CT scan showed retroperitoneal mass that invaded inferior vena cava with no distant metastasis (Figure 1A). Topotecan and then Liposomal Adriamycin that were poorly tolerated. The disease progressed further locally causing mass effect on the right ureter and spread to the lungs (Figure 1B).  The area of the cribriform/papillary growth pattern (Figure 2 images 1,2).
case_images: H&E of the excised retroperitoneal lymph node showing poorly differentiated carcinoma, forming cribriform/papillary growth pattern [image 1] and focal clear cell changes [image 2]. Complete loss of nuclear expression of MLH-1 [image 3] and PMS-2 [image 4]. Intact expression of MSH-6 [image 5] and MSH-2 [image 6]. Low power section demonstrates invasive malignant tumor-infiltrating tissue by a solid sheet of tumor cells with obvious voluminous clear cytoplasm (hematoxylin and eosin stain, 4x, [image 7]. High power section demonstrates malignant tumor composed of large voluminous clear cytoplasm, distinct margins, enlarged angulated pleomorphic hyperchromatic bizarre nuclei with prominent nucleoli (hematoxylin and eosin stain, 40x, [image 8].
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case_images: PMC6875561_01_OTT-12-9965-g0003.jpg
case_images: F0002
case_images: The mass was excised together with inferior vena cava angioplasty and the pathology showed lymph node metastasis with poorly differentiated carcinoma, forming cribriform/papillary growth pattern (Figure 2: image 1) and focal clear cell changes (Figure 2: image 2) in favor of endometrial primary. The area of the cribriform/papillary growth pattern (Figure 2 images 1,2). Complete loss of nuclear expression of MLH-1 (Figure 2 image 3) and PMS-2 (Figure 2 image 4). Intact expression of MSH-6 (Figure 2 image 5) and MSH-2 (Figure 2 image 6). The area of the clear cell tumor demonstrated obvious voluminous clear cytoplasm (Figure 2 image 7). High power section demonstrates malignant tumor composed of large voluminous clear cytoplasm, distinct margins, enlarged angulated pleomorphic hyperchromatic bizarre nuclei with prominent nucleoli (Figure 2 Image 8). 
case_images: EEG background presented with diffuse delta slowing, but without hemispheric asymmetry nor epileptiform discharges. The impression picture was in favor of severe encephalopathy.
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case_images: F0003
case_images: Complete loss of nuclear expression of MLH-1 (Figure 2 image 3) and PMS-2 (Figure 2 image 4).
case_images: (A) Bone marrow aspirate (100x) showing enhanced megakaryopoiesis and anisocytosis with some small-hypolobated megakaryocytes and few forms showing hyperlobulation with widely separated nuclear lobes (arrow). (B) vWF immunostain highlights active megakaryopoiesis. (C) Bone marrow biopsy (H&E, 10x): Normocellular for age with trilineage hematopoiesis and active megakaryopoiesis. No evidence of BM infiltration by carcinoma cells.
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case_images: PMC6875561_01_OTT-12-9965-g0005.jpg
case_images: F0004
case_images: Complete loss of nuclear expression of MLH-1 (Figure 2 image 3) and PMS-2 (Figure 2 image 4).
case_images: Blood counts from 01.08.2017 to 24.09.2017 showing the WBC, Hemoglobin and the Platelet curves during the period of follow-up.
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case_images: F0005
case_images: Intact expression of MSH-6 (Figure 2 image 5) and MSH-2 (Figure 2 image 6). During the following days the WBC reached 1 x 109/L, platelets 10 x 109/L and Hb 7 g/dL (Figure 5).
case_images: Patient's three-generation pedigree.
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case_images: F0006
case_images: Later, one of the patient's sisters whose unaffected 51 years old (Figure 6.
case_images: PMC6875561_02
case_images: Patient's three-generation pedigree.
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case_images: PMC6875561_02_OTT-12-9965-g0007.jpg
case_images: F0006
case_images: Later, one of the patient's sisters whose unaffected 51 years old (Figure 6.