Figure 1.

H & E staining.A. Intermediate power view showing lymph node was replaced by a population of large cells with scattered background small lymphocytes. B. High power views of tumor cells demonstrated typical nuclear groove (green arrows), prominent nucleoli (red arrow), and abundant eosinophilic cytoplasm. Mitotic figures can be easily found (black arrows). Immunohistochemistry. C-H. Tumor cells demonstrated strong positivity for CD1a (C), langerin (D), S100 (E) and CD4 (F). Tumor cells showed positivity for cell cycle regulator p53 (G). Tumor cells were labeled more than 50% of cell proliferation index marker Ki-67 (H).