Figure 2

Microscopic analysis of biopsy of Merkel cell carcinoma. (A) Photomicrograph showing that Merkel cell carcinoma tumor cells are surrounded by intense inflammation with lymphocytes, plasma cells, and histiocytes. Proliferation of basophilic cells with round uniform nuclei, scanty cytoplasm, patchy chromatin and inconspicuous nucleoli (black arrows). (H&E, ×400). (B) Photomicrograph showing the same tumor stained for CK20. There is strong expression of CK20 in the cytoplasm and membrane of MCC. C Immunostaining with CAM5.2 showing characteristic para-nuclear accentuation. (D) NSE positive suffusion expresstion was localized on in the cytoplasm and membrane. (IHC, ×400).