Metastatic Malignant Melanoma Presenting as an Appendiceal Mucocele
Figure 3
Microscopic examination: (a) solid cords and nests of tumor cells fill the appendiceal lumen and replace the appendiceal mucosa and submucosa with partial extension to the muscularis, no involvement of the serosa; (b) tumor cells with abundant eosinophilic cytoplasm, some of which are vacuolated, with pleomorphic nuclei, prominent nucleoli, and atypical mitosis (Hematoxylin and eosin staining, (a) x200; (b) x400). (c) Tumor cells strongly express HMB45, and (d) S-100 (HMB45 and S-100 immunostaining, x400).
