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case_images: (A) The timeline of the whole management course of the patient with occult breast cancer. (B) One-year follow-up US features with thyroid metastases from her occult breast cancer (arrows show the metastasis areas which manifested as diffuse faveolate changes in the US).
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case_images: Cerebellar metastasis was diagnosed during the chemotherapy treatment ( Figure 1A ). Taxol liposome 210 mg d1 + Herceptin 318 mg d1 and four cycles of Herceptin 318 mg per 3 weeks as we monitored the progress in the thyroid. The sizes and hypoechoic areas of the thyroid gland changed repeatedly during this process ( Figure 1B ). The size of the diffuse faveolate area of the thyroid was obviously shrunk as shown in the final US examination.
case_images: (A) Cytology smear of the thyroid faveolate echo area in the US (Wright-Giemsa x1,000). (B) Histochemical staining of the biopsy specimen from thyroid (hematoxylin-eosin stain x400).
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case_images: The cytology showed a mass of tumor cells found in the smear ( Figure 2A ). Figure 2B ). Further, negative immunohistochemistry (IHC) results of thyroid transcription factor 1 (TTF1), TPO, and TG showed that the tumor cells were not derived from the thyroid ( Figure 3 ).
case_images: Immunohistochemical staining of the biopsy specimen from the thyroid (x400). TTF1-; TPO-; TG-; GATA-3-.
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case_images: Figure 2B ). Further, negative immunohistochemistry (IHC) results of thyroid transcription factor 1 (TTF1), TPO, and TG showed that the tumor cells were not derived from the thyroid ( Figure 3 ).
case_images: Immunohistochemical staining of the biopsy specimen from the thyroid (x400). Ki-67+ (60%); GCDFP15+; mammaglobin+; CD34+; P53+; E-cadherin+; HER2+; ER-; PR-.
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case_images: The positive staining of GATA3, gross cystic disease fluid protein 15 (GCDFP15), mammaglobin, CD34, P53, and E-cadherin confirmed that these neoplasms were infiltrating ductal carcinoma derived from the breast ( Figure 4 ). The molecular subtype of our OBC case turned out to be human epidermal growth factor receptor 2 (HER2) positive due to the positive IHC result for HER2, negative estrogen receptor (ER), and negative progesterone receptor (PR) ( Figure 4 ).