Well-Differentiated Neuroendocrine Tumors with a Morphologically Apparent High-Grade Component: A Pathway Distinct from Poorly Differentiated Neuroendocrine Carcinomas

Abstract

Mixed grades can occur in WD-NETs, which are distinguished from PD-NECs by their unique phenotype, proliferative indices, and the genotype. This phenomenon of mixed grade in WD-NET provides additional evidence to the growing recognition that the current WHO G3 category contains both WD-NETs as well as PD-NECs.