case_images: PMC11810719_01
case_images: 18F-FDG-PET/CT scan showing hypermetabolic uptake in the (A, B) skin (white arrows) and (C) left parotid gland. A whole-body scan (D) is also shown. The patient's name and date of birth have been omitted for confidentiality reasons.
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case_images: PMC11810719_01_fonc-15-1512000-g001.jpg
case_images: f1
case_images: Further investigation with 18F-FDG-PET/CT scan revealed hypermetabolic foci in the skin and left parotid gland (potentially accounting for the observed Bell's palsy) ( Figure 1 ), as well as multiple other sites (lung, bones, muscles, peritoneum and multiple lymph nodes (cervical, mediastinal, portal)).
case_images: Microscopic examination of a biopsy from a skin lesion revealed infiltration of fat and striated muscle tissue (white asterisk) from an enteric type adenocarcinoma (tubular and cribriform pattern) (A) (H&E staining). Immunohistochemical analysis showed that the neoplastic cells expressed (B) CK20 but not (C) CDX-2, CK7 and TTF-1 (data not shown for CK7 and TTF-1). These features, combined with the patient's history, were more compatible with a metastatic colorectal carcinoma. (D) Proliferation rate, as expressed by ki67 positivity, was almost 100%. Images are shown at 200x magnification. DAB as chromogen and hematoxylin as counterstain. CK, Cytokeratin; H&E, Hematoxylin and Eosin.
case_images: fonc-15-1512000-g002.jpg
case_images: PMC11810719_01_fonc-15-1512000-g002.jpg
case_images: f2
case_images: BRAF V600E mutation. Biopsies of the skin lesions revealed infiltration by a low-grade enteric type adenocarcinoma, consistent with the morphologic characteristics of the primary tumor ( Figure 2A-C ). Notably, metastatic cancer cells exhibited an extremely high proliferation rate (ki67 positivity: 95%) ( Figure 2D ).
case_images: Timeline of events and case progression.
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case_images: PMC11810719_01_fonc-15-1512000-g003.jpg
case_images: f3