case_images: PMC11807832_01
case_images: A protruding bright red mass (red arrow) on the right front border of the tongue.
case_images: fonc-14-1473211-g001.jpg
case_images: PMC11807832_01_fonc-14-1473211-g001.jpg
case_images: f1
case_images: Examination revealed a 2-cm bulging mass with a bright red color on the front right of the tongue ( Figure 1 ).
case_images: Hematoxylin and eosin staining of the tongue lesion reveals: (A) clusters of tumor cells located within the mucous membrane (red box) and submucosal layer, adjacent to the squamous epithelial tissue of the tongue (x 100); (B) tumor cells organized in clusters, supported by a dense capillary network (x 100); (C) tumor cells with large, hyperchromatic nucleoli (x 200); and (D) tumor cells exhibiting clear cytoplasm and pathological mitotic figures (red arrow) (x 400). Immunohistochemical staining results: positive staining for (E) vimentin, (F) EMA, (G) CD10, and (H) PAX-8, with negative staining for (I) PAX-2 (immunohistochemistry; E-I, x 400).
case_images: fonc-14-1473211-g002.jpg
case_images: PMC11807832_01_fonc-14-1473211-g002.jpg
case_images: f2
case_images: An excisional tissue biopsy was performed, revealing lobulated and nested epithelial cell clusters with moderate dysplasia and frequent mitotic figures in the lamina propria ( Figures 2A-D ). Immunohistochemical analysis showed positivity for vimentin, epithelial membrane antigen (EMA), CD10, and PAX-8, while being negative for PAX-2 ( Figures 2E-I ), calponin, S-100 protein, periodic acid-Schiff with diastase (PAS-D), P63, P40, and CK7.
case_images: (A) Contrast-enhanced head and neck CT scan showing an unevenly enhanced lesion (red arrow) on the patient's tongue. (B) Chest CT scan demonstrating spiculated nodules (red arrow) of varying sizes in both lungs. (C) Abdominal contrast-enhanced CT scan illustrating an irregular mass (red arrow) in the left kidney. (D) Size of target lesions (red arrow) in the lungs prior to treatment. (E) Size of target lesions (red arrow) in the lungs after 7 months of treatment, evaluated as stable disease (SD). (F) Following discontinuation of treatment, a new metastatic lesion (red arrow) appeared, and target lesions were evaluated as progressive disease (PD).
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case_images: PMC11807832_01_fonc-14-1473211-g003.jpg
case_images: f3
case_images: A head and neck CT scan with contrast revealed an unevenly enhanced lump on his tongue ( Figure 3A ), while a chest CT identified multiple high-density nodules in both lungs, suspected to be lung metastases ( Figure 3B ). A contrast-enhanced CT of the abdomen revealed a lumpy mass measuring approximately 9.8 cm x 8.6 cm in the left kidney, with heterogeneous enhancement typical of RCC ( Figure 3C ).
case_images: Whole-body PET/CT scan findings: (A) Soft tissue mass with 18F-FDG hypermetabolism in the left kidney (red arrow). (B) Soft tissue density lesion with 18F-FDG hypermetabolism at the right anterior border of the tongue (red arrow). (C) Multiple 18F-FDG hypermetabolic nodules and masses in the right lung (red arrow). (D)
  18F-FDG hypermetabolic nodule in the left lung (red arrow).
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case_images: PMC11807832_01_fonc-14-1473211-g004.jpg
case_images: f4
case_images: The scan also revealed tongue metastasis (SUVmax 9.4) and bilateral lung metastases (SUVmax 4.8 and 6.5) ( Figure 4 ).