case_images: PMC6193799_01
case_images: H&E stain demonstrating a mass at the tip of the appendix. H&E, hematoxylin and eosin.
case_images: 10-1055-s-0038-1672166-i180403cr-1.jpg
case_images: PMC6193799_01_10-1055-s-0038-1672166-i180403cr-1.jpg
case_images: FI180403cr-1
case_images:  Microscopy demonstrated a 5-mm well-differentiated neuroendocrine tumor in the tip of the appendix ( Fig. 1 ), which extended into muscularis propria.
case_images: H&E stain demonstrating infiltrating neuroendocrine cells and nests confirmed by positive synaptophysin staining (inset). H&E, hematoxylin and eosin.
case_images: 10-1055-s-0038-1672166-i180403cr-2.jpg
case_images: PMC6193799_01_10-1055-s-0038-1672166-i180403cr-2.jpg
case_images: FI180403cr-2
case_images: On hematoxylin and eosin (H&E) staining, nests of neuroendocrine cells could be seen infiltrating into the appendix wall and involved the proximal resection margin, and findings were confirmed on synaptophysin staining ( Fig. 2 ). 