case_images: PMC11066275_01
case_images: (A) Breast US images revealed a hypoechoic irregular mass in the breast left upper quadrant, with a size of about 23x25x19mm, the boundary was not uneven and no strong punctate echo was observed. The combination of contrax-enhanced ultrasound suggested the mass uneven enhancement in the arterial phase, unsmooth boundary, slow regression in the venous phase, and obvious enlargement in the lesion area. (B) The whole excised tissue of the left breast. (C) The resected specimen showed leaf-like (phyllodes) epithelial pattern (HEx100). (D) Stromal overgrowth, tumor giant cells and many abnormal mitosis are noted (HEx100). (E) The stroma showed a tumor osteoid rimmed by tumor cells along with osteoclastic giant cells, osteosarcoma differentiation (HEx100). (F) The section showed tumor cells with chondrosarcomatous differentiation, the chondrocyte density is different, the cell atypia is obvious, the nuclear mitosis and cartilage islands can be observed (HEx100).
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case_images: PMC11066275_01_fonc-14-1372710-g001.jpg
case_images: f1
case_images: The color ultrasound of the breast showed that there was a low-echo mass located at the edge of the mammary gland at 2 points in the left upper quadrant, with a size of 23x25x19mm, the boundary was not clear, and the shape was irregular, and no strong punctate echo was observed ( Figure 1A ). Pathological examination results: the size of the left breast was 23x18x3.0cm, and the fusiform skin was attached, the size of which was 19.5x7.0cm ( Figure 1B ). The tumor has a lobulated mass ( Figure 1C ), which is composed of epithelial and stromal components. The epithelial cells are columnar or cuboidal without obviously atypia. Stromal cells are fusiform, the cytological atypia was obvious ( Figure 1D ), with 10 mitotic images/10HPF. Tumor cells surrounded trabeculae, and the cell atypia was significant, showing mitotic images ( Figure 1E ). Chondrocytes of different density were observed with obvious cell atypia, and mitotic images ( Figure 1F ). (3) Immunohistochemistry: Spindle tumor cells ER(-), PR(-), HER-2(-),
case_images: (A) Positive staining with CD34 in atypical stromal cells (x100). (B) The positive staining with Ki-67 in atypical stromal cells is about 60% (x100). (C) The positive staining with p53 in atypical stromal cells is about 90% (x100). (D) MDM2 is negative expressed in stromal cells (x100). (E) SATB2 is positively stained in atypical stromal cells (x100). (F) CD68 is expressed in osteoclastic giant cells (x100).
case_images: fonc-14-1372710-g002.jpg
case_images: PMC11066275_01_fonc-14-1372710-g002.jpg
case_images: f2
case_images: P63(-), P40(-) were all negative. CD34:(+), SATB2(+), P53(90% strong), CD68 (+), Ki-67(LI: about 60%) ( Figure 2 ). (4) No ductal carcinoma in situ was found in the breast, and no metastasis were found in axillary lymph nodes. Pathological consultation advice of Union Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology: Malignant (breast) phyllodes tumor with osteosarcoma and chondrosarcoma differentiation was considered.
case_images: FISH showed USP6 positively rate was 2% which indicated negative expression on sections (x1000).
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case_images: PMC11066275_01_fonc-14-1372710-g003.jpg
case_images: f3
case_images: FISH results were interpreted independently by two experienced pathologists: 200 neoplastic cells in a blind fashion using an Olympus BX53 fluorescence microscope (Japan) were counted, the distance between red signal and green signal was > 2 signal points as positive cells, and the proportion of positive cells was > 10% as positive for separation and rearrangement. FISH showed USP6 positively rate was 2% which indicated negative expression on sections ( Figure 3 ).