case_images: PMC10540842_01
case_images: (A) Nodular area with central low density in the left side of the thymus, measuring roughly 32 mm long axis indicative of mediastinal seminoma (yellow indicator). (B) Computed tomography of axial chest demonstrates anterior mediastinal mass (red arrow).
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case_images: f1
case_images: CT chest with contrast revealed a heterogeneous anterior mediastinal soft tissue nodule located within the thymus ( Figure 1 ).
case_images: (A) Section of thymus shows cystic degeneration at the right side of the image (white space) and a rim of thymus showing intact, normal Hassel's corpuscles and a diffusely infiltrative malignant process. Tumor cells are present as single, dispersed cells, as well as cords and clusters, in a background of lymphocytes and thymic epithelial cells. Although there is cystic degeneration, the diffusely infiltrative growth pattern results in more of thickening of the thymic epithelium rather than a discrete mass. H&E stain, 20x magnification. (B) Higher magnification showing tumor infiltrative as single cells, cords, and clusters between lymphocytes, thymic epithelium, and Hassel's corpuscles. The tumor cells are large, contain clear to eosinophilic cytoplasm, and have large, round nuclei with prominent nucleoli. H&E stain, 40x magnification. (C) Pancytokeratin stain shows diffuse staining in the normal thymic epithelium in the lower left portion of the image. In contast, clusters of tumor cells show focal, punctuate staining. AE1/AE3 stain, 40x magnification. (D) Clusters and isolated seminoma cells show nuclear posibility with the germ cell marker OCT3/4. OCT3/4 stain, 40x magnification. (E) Clusters and isolated seminoma cells show nuclear positivity with the germ cell marker SALL4. SALL4 stain, 40x magnification. (F) Background thymic epithelium stain positively with p63 while the seminoma cells that are present in clusters are negative. p63 stain, 40x magnification. H&E, Hematoxylin and eosin; AE1/AE3, cytokeratin stain; OCT 3/4, octamer-binding transcription factor 4; SALL4, spalt like transcription factor 4.
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case_images: PMC10540842_01_fonc-13-1156566-g002.jpg
case_images: f2
case_images: Pathology revealed seminoma with lymphoid hyperplasia and cystic change with IHC positive for pancytokeratin, CD117, octomer-binding transcription factor 3/4 (Oct3/4), placental alkaline phosphatase (PLAP), and spalt like transcription factor 4 (SALL4) ( Figure 2 ).
case_images: A detailed diagnosis and treatment timeline of mediastinal seminoma with paraneoplastic anti-Hu encephalitis.
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case_images: f3
case_images: He works with physical and occupational therapists and is now able to walk with walker ( Figure 3 ).