Figure 2From: A patient presenting with acute abdomen due to metastatic small bowel melanoma: a case report (a) Invasion of the intestinal wall from marked atypical neoplastic cells containing melanin pigmentation (hematoxylin and eosin ×100); (b) immunohistochemically, tumor cells were reactive for S-100 protein, (c) HMB-45, and (d) melan-A (3,3'-diaminobenzidine ×100). Back to article page