POMC and Cushing syndrome: According to the literature, functional TNETs account for about 12%, with ACTH-secreting and carcinoid syndrome being the most common types, while Cushing syndrome accounts for 11.8%.2,12,13 Similarly, we found that 11.8% of TNETs were functional tumors, but only 5 cases of functional TNETs with ACTH-secreting, accounted for 4.9%.