Neuroendocrine Tumors

**Definition:** Tumors whose cells possess secretory granules and originate from the neuroectoderm, i.e., the cells of the ectoblast or epiblast that program the neuroendocrine system. Common properties across most neuroendocrine tumors include ectopic hormone production (often via APUD CELLS), the presence of tumor-associated antigens, and isozyme composition.

**Tree numbers:** - C04.557.465.625.650 - C04.557.580.625.650