case_images: PMC6636445_01
case_images: Lymph node biopsy. Sections show high-grade, pleomorphic malignant cells in a background of small lymphocytes (H&E, 200x).
case_images: CRIHEM2019-2587597.001.jpg
case_images: PMC6636445_01_CRIHEM2019-2587597.001.jpg
case_images: fig1
case_images: The patient underwent an excisional lymph node biopsy on July 24, 2009, that revealed replacement of the lymph node by highly pleomorphic cells with prominent nucleoli and abundant cytoplasm, suggestive of high-grade metastatic carcinoma (Figure 1).
case_images: Lymph node biopsy. The malignant cells are strongly positive with antibodies to cytokeratin, indicating epithelial lineage and supporting the diagnosis of carcinoma (cytokeratin AE1/AE3, 200x).
case_images: CRIHEM2019-2587597.002.jpg
case_images: PMC6636445_01_CRIHEM2019-2587597.002.jpg
case_images: fig2
case_images: Immunohistochemical evaluation showed that 100% of the cells were positive for cytokeratin (CK) (Figure 2) but negative for CK7, CK20, thyroid transcription factor-1 (TTF-1), melanoma antigen (Melan-A), CD30, and leukocyte common antigen.