case_images: PMC10673346_01
case_images: a Mammography revealed a lobulated and high-density mass in the left lower inner quadrant of the breast. b Ultrasonography showed a well-circumscribed and amorphous mass in the right breast that was 2.7 cm in size, had well-defined margins, enhanced posterior echoes, halo, and low-level internal echoes. c MRI revealed an amorphous mass with a pattern of early enhancement and washout. There was extensive ductal spread and a daughter nodule in the outside forward of the mass (arrow). d Pathological findings of core needle biopsy, showing atypical spindle cells with cobblestone appearance. e HER2 was overexpressed on the surface of the cancer cells (score of 3+). f CK5 was expressed on the part of the cancer cells.
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case_images: F1
case_images: Mammography showed a lobulated and high-density mass in the left lower inner quadrant of the breast (Fig. 1a). The mass had well-defined margins, enhanced posterior echoes, a halo, and low-level internal echoes (Fig. 1b). Contrast-enhanced magnetic resonance imaging (MRI) showed a 3.1 cm amorphous mass with a pattern of early enhancement and washout in the right breast (Fig. 1c).
case_images: a Ultrasonography after three courses of Tmab+Pmab+DTX showed the tumor growth to 3.3 cm in size. b Ultrasonography after two courses of EC showed that the tumor was enlarged and out of frame. c MRI showed the tumor with internal degeneration suspected of necrosis.
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case_images: F2
case_images: Tmab+Pmab+DTX, ultrasonography showed the tumor growth to be 3.3 cm in size (Fig. 2a). The patient underwent two courses of epirubicin + cyclophosphamide (EC) as the next NAC regimen. However, the tumor was out of frame in ultrasonography (Fig. 2b) and grew to 3.8 cm in size with internal degeneration suspected of necrosis in MRI (Fig. 2c).
case_images: a Surgical specimen showed fibrosis and hemorrhage around the tumor. b, c The postoperative pathological results suggest that the tumor cells were pleomorphic and proliferated in sheets with necrosis and keratinization. d HER2 was weekly expressed on the surface of the cancer cells (score of 2+).
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case_images: F3
case_images: The pathological tumor size was 3.5 x 2.5 cm (Fig. 3a), and the sentinel lymph node appeared to be normal. The postoperative pathological result of the surgical specimen showed that the tumor cells were pleomorphic and proliferated in sheets with necrosis and keratinization (Fig. 3b, c), leading to the diagnosis of metaplastic carcinoma (squamous cell carcinoma).