fig2

Figure 2. Well-differentiated neuroendocrine tumor (G1) of the ileo-cecal valve. (A) Mucosal ulceration (arrow, X10); (B) positivity of neoplastic nests for Chromogranin A (CgA) in the submucosa (X10); (C) muscolar layer neoplasitic invasion and positivity for CgA (X4); (D) piercing serosa positivity for CgA (arrow, X10); (E) serotonin stains the enterochromaffin cells (EC) (X20); (F) mindbomb homolog 1/ki-67 proliferation index below 2% (arrow, X40)