Fig. 3
From: Late-stage diagnosis of carcinoid heart disease due to lack of access to health care
Immunohistochemical stains demonstrated neuroendocrine origin. Positive membranous staining with CD56 (top left, see the text label), membranous and cytoplasmic staining with synaptophysin (top right, see the text label) and chromogranin (bottom left, see the text label) were seen. A low ki67 proliferation index of 2% was present in the tumor cells (bottom right, see the text label) consistent with a diagnosis of well-differentiated neuroendocrine tumor (100 × magnification)